Genesis 3:15 has often been called the protoevangel, the first record of the gospel. Or it is called the Mother Promise, the promise that gives birth to all other promises in Scripture. God said to the serpent, the devil: “I will put enmity between you and the woman, and between your seed and her Seed; He shall bruise your head, and you shall bruise His heel.”
What is enmity?
Apart from Genesis 3:15, we seldom encounter this word ‘enmity’ in the Bible and use it even less in our daily conversations. What does it mean? My Oxford defines enmity as “a state of being an enemy, hostility.” Various of Hebrew lexicons give ‘hostility’ as an alternate rendering for this same word in Hebrew.  Since the word ‘’hostility’ is more common to us, I will use it instead of ‘enmity.’
This hostility is appointed by God
That’s quite something, isn’t it? After all, we are more accustomed in our day to hearing God described as love (1 John 4:8, 16).  But in Genesis 3:15 God says, “I will put enmity…”. This hostility is appointed by God. And this means two things. In the first place, it is God’s will that this hostility exist, and to remove this hostility is to act contrary to God’s will. In the second place, the fact that God appoints this hostility means that this hostility is good, for all that God does is good. To remove this hostility is evil.
This hostility leads to war
The Hebrew word ‘enmity’ which is used in Genesis 3:15 is used in only four other places in the Old Testament. In Numbers 35:21, 22  this word is used to describe the pre-meditated hostility which impels a man to strike another man, killing him. In Ezekiel 25:15  it describes the old hostility which induced the Philistines to attack God’s people with vengeance. In Ezekiel 35:5  this word describes the hostility of the Edomites against the Israelites, which led them to raise the sword against the Israelites and to shed their blood. Thus this enmity or hostility which God appointed in Genesis 3:15 leads to fighting, to war.
Hostility and War between whom?
In rebelling against God in paradise the human race, under the headship of Adam, chose to side with Satan against God. As a result the relationship between God and man was broken, and a relationship between Satan and man was formed In as much as Satan sowed the seed of rebellion in man’s mind and heart, he is called the father of those who rebelled, and they are called his children (cf. 1 John 3:10)  who now do his will willingly (cf. John 8:44). 
In His grace, God decided that He would redeem a part of the fallen human race, and draw to Himself again those who had alienated themselves from Him. He would renew His original covenant with mankind, providing a new head and representative in this covenant, who is our Lord Jesus Christ, whom the Father would send into this world, to be born as the Seed of woman to whom Genesis 3:15 ultimately refers as the one whose heel would was bruised by the serpent, but who in turn would crush the serpent’s head. By way of this covenant, God would be their Father, and they would be His children.
Thus the war is between the serpent and his seed (who in 1 John 3:10 are called the children of the devil), and the woman and her seed (who in 1 John 3:10 are called in the children of God). 
Two rulers at war
As a result of the hostility which God has placed between these two factions, there is war between these two rulers and the two realms they command.
At the head of one faction is Satan and his demons. Satan is called ‘the ruler of this world” (cf. John 12:31; 14:30),  and he and his demons are together called “world rulers of this dark age” (cf. Eph 6:12)  Satan is described as “the prince of the power of the air, the spirit who now works in the sons of disobedience” (Eph 2:2). Satan is described in Scripture as possessing rule, authority and power (cf. 1 Cor 15:24; Eph 6:12).  With the exception of those who have been redeemed by Christ, the whole world is under his dominion. As the apostle John writes 1 John 5:19 “We know that we are of God, and the whole world lies under the sway of the wicked one.”
At the head of the other faction is Jesus Christ, who is both King of the church, and King of creation. As King of Creation He has been given “all authority…in heaven and on earth” (Matt. 28:18) with a view to gathering, defending and preserving His Church.. He is also entitled, “King of kings and Lord of lords” (cf. Rev 17:14; 19:16) and also “the Ruler of the kings of the earth” (Rev 1:5). Under Christ’s dominion and rule are all those whom He has redeemed with His blood. He rules them by His Word and Spirit, and they bow the knee before Him, and confess that He is their Lord and Master.
Christ’s kingship over the world is only temporary. In 1 Corinthians 15:24-28 we read “Then comes the end, when He delivers the kingdom to God the Father, when He puts an end to all rule and all authority and power. 25 For He must reign till He has put all enemies under His feet. … 28 Now when all things are made subject to Him, then the Son Himself will also be subject to Him who put all things under Him, that God may be all in all.” In simple words, Christ as Redeemer will retain his kingship over creation only as long as it takes to destroy every hostile power on earth. At that time, Christ the Redeemer will hand the rule of creation back to the Father, and will place Himself under the Father’s authority.
Two realms at war
The realm over which Satan rules is referred to in Scripture as “the world” (cf. John 12:31, 14:30 and 16:11).  This does not mean that the realm of Satan is merely a physical or earthly realm, for it is ruled and empowered by the spiritual hosts of wickedness in the heavenly places (cf. Eph 6:12). To this realm belongs the greater part of humanity and every institution which is under Satan’s dominion and rule (cf. 1 John 5:19),  which is alienated from God and lives in rebellion against God.
The realm over which Christ rules is referred to in Scripture as “the kingdom of heaven”, or the “kingdom of God”, or “the kingdom of Christ.” It is not a kingdom of this world (cf. John 18:36).  That is, it is not a physical kingdom defined by physical borders and defended by men with physical weapons. It is a spiritual realm, to which belongs every person and every institution which is ruled by Christ through His Word and Spirit. The church plays a fundamental role in the kingdom, for the church admits and expels men from the kingdom. The church also equips the citizens of Christ’s kingdom with the spiritual armour (cf. Eph 6:11-17)  which they need to wage war against the realm of the evil one.
Because of the hostility which God has appointed between these two realms, the kingdom of heaven (which certainly includes the church) and the world are at war with each other.
The objective of this hostility and war
In a word, the objective is to conquer. In Revelation 6:2  we see Christ sitting upon a white horse, “and he went out conquering and to conquer.” In Revelation 11:7 we see the antichristian world (portrayed as a beast) and the Church (portrayed by two witnesses). The antichristian world makes war against the church, and for the greater part will overcome the church leaving only a small remnant of believers on earth. In Revelation 13:7 we are again shown the beast that seeks to make war on the saints, and strives to conquer them. In Revelation 17:14 we see that the victory ultimately belongs to Christ who in the end will conquer all, “for He is Lord of lords and King of kings; and those who are with Him are called, chosen, and faithful.”
Conquering does not necessarily mean destruction. In earthly wars opposing countries have often fought over land. Their purpose was not to destroy the land. Rather, they sought to possess that land. They wanted to control it. They wanted to reap the harvest of that land.
Such is the case in the war between the kingdom of heaven and the world. Satan’s intent is not merely to destroy mankind and to destroy the earth. Rather, his goal is to conquer with a view to ruling the hearts of men, ruling the world, reaping the rotten fruits borne by corrupt men.
In the same way, God’s intent in appointing this hostility and in sending Christ to make war against the world is not simply to destroy the world. He came first of all to save. But salvation comes by conquering—conquering the lie by the truth, conquering hatred with love, conquering evil with good, conquering rebellion against God with obedience to God. This is why Christ is portrayed as the conquering king who goes out to battle armed with a sharp two-edged sword that issues from His mouth (cf. Rev 1:16; 2:16). His weapon is the sword of the Spirit, which is the Word that cuts both to salvation and condemnation. By means of the Word, empowered by the Spirit, the minds of men are powerfully though pleasantly enlightened and their hearts renewed. They see the evil character of their ruler, Satan. They see the misery of being dominated by him. They see the destruction that awaits his realm. At the same time they see the goodness of God. They see the blessedness that comes from submitting to God. They see that the victory ultimately belongs to God. The result is that men of the world cross the battle line. They abandon their allegiance to Satan, renounce their citizenship in the world. They defect to the kingdom of heaven, and rally behind Christ their King. By means of the Word empowered by the Spirit Christ delivers all those whom the Father has given him from the power of darkness and conveys theminto His kingdom (cf. Col 1:13). 
At the end of days, when all of God’s elect have been transferred from the realm of Satan into the Kingdom of God, the war will change its character. Instead of conquering to save, Christ and the saints will conquer to destroy. In the end a great battle will be fought at a place figuratively called Armageddon (cf. Rev 16:16).  The two realms will fight with the intent of destroying the other completely. Although the final battle is still a thing of the future, the outcome is already certain. Christ has in principle overcome Satan and the world (cf. John 12:31, 16:11, 16:33, 1 John 5:4, Rev 12:10).  The victory belongs to Christ and to those who are His. In the end, there will be only one realm on earth, the kingdom of heaven.
This holy hostility demands separation and non-conformity…
The two rulers (Christ and Satan) and the two realms (the kingdom of heaven and the world) are diametrically opposed to each other. The one is a kingdom of righteousness; the other a kingdom of lawlessness. The one is a kingdom of light; the other a kingdom of darkness. Because they are diametrically opposed to each other, there can be no fellowship. As Paul states clearly in 2 Corinthians 6:14-17 “…What fellowship has righteousness with lawlessness? And what communion has light with darkness? And what accord has Christ with Belial? Or what part has a believer with an unbeliever? …Therefore ‘Come out from among them and be separate, says the Lord….’”
In Revelation 18:4 a similar cry is heard: “Come out of her, my people, lest you share in her sins, and lest you receive of her plagues.” The reference is to the harlot called Babylon, which “represents the world as the centre of antichristian seduction”  “which by means of…[industry, commerce, art, culture, etc]…seeks to entice and seduce the believer, that is, to turn him away from God. It is the world as the embodiment of the ‘lust of the flesh, the lust of the eyes, and the vainglory of life’ (1 Jn. 2:16).” 
The kingdom of heaven is being established in the midst of this world. As such, we, the citizens of the kingdom of heaven, are in the world, but we are not of the world (cf. John 17:16). We don’t “fit” in the world. Our thoughts, our aims, our hopes, our joy, our conduct are totally different. We do not conform to this world which reflects the image of Satan (cf. John 8:44), but we are transformed by the renewing of our mind (cf. Romans 12:2)  into the glorious image of God (cf. 2 Cor 3:18).  Therefore we are and must remain aliens in this world, strangers or sojourners (cf. 1 Peter 2:11). 
We do not form friendships with the people of the world, for that would be tantamount to committing adultery. This clear warning is stated by James: “Adulterers and adulteresses! Do you not know that friendship with the world is enmity with God? Whoever therefore wants to be a friend of the world makes himself an enemy of God. Or do you think that the Scripture says in vain, ‘The Spirit who dwells in us yearns jealously’?”(James 4:4,5). Friendship refers to personal relationships, that is, relationships with people, not merely with things or actions. The words ‘friend’ and ‘enemy’ describe personal relationships. We enjoy friendship with God, providing we do not form friendships with the people of the world. But if we become friends with the people of the world, we become an enemy of God.
…and forbids us to love the things of the world
In 1 John 2:15-17 the apostle writes, “Do not love the world or the things in the world. If anyone loves the world, the love of the Father is not in him. For all that is in the world — the lust of the flesh, the lust of the eyes, and the pride of life — is not of the Father but is of the world. And the world is passing away, and the lust of it; but he who does the will of God abides forever.”
Does this mean that everything that originates from the world is evil, and must be avoided? This question is important in the context of culture, science and technology. Is every aspect of culture to be regarded as evil and therefore avoided? Must we abstain from using or benefiting from the developments of science and technology?
In a recent catechism class, we discussed the depravity of man. We saw from the Scriptures that man’s mind has become dark, and his heart corrupt, and his will stubborn. Man lost many of the wonderful virtues and abilities with which he was created, which enabled him to reflect God. But man has not lost all the abilities with which he was created. God allowed fallen men to retain the ability to think and reason, and to retain some notions of what is beautiful and noble. Man is able to search, to understand and to develop various aspects of creation. As a result fallen man is still able to complete some aspects of the cultural mandate. He is able to develop the world, and discover some of the wonderful potentials that God has created in this world. Great achievements have been made in the realm of medicine and technology. Sadly, because of his depravity, fallen man uses all that he discovers and “creates” for evil intents and purposes, but these achievements are not evil in themselves. As Christians we can use and benefit from these achievements and “creations.” Over the history of the world wonderful musical instruments have been made which make pleasing sounds.  Techniques in art and design have been developed which can lead to beautiful “creations.” We can appreciate fine music and art. We can appreciate a nicely designed building. In these things we see a reflection of the wisdom, the goodness, the majesty of the creator who endowed man with these qualities that dimly reflect His own perfections.
Recently I read a book which addresses the question of worldliness with respect to music. At the very beginning the author acknowledges that the debate about worldliness “demands clarification of terms and a scriptural definition of worldliness, rather than an all-inclusive one that fails to make distinctions between that which simply originates from the world and that which originates in the world but stands in clear antipathy to biblical standards.” He says, “When taken together, Romans 12:2 and 1 John 2:15-17 forbid the adoption of patterns of thinking, modes of behaviour, attitudes, philosophies, outlooks, grids of evaluation, affections, gratifications, priorities, and value systems that are sinful and a manifestation of the world’s perverted understanding of what is true, good, and brings lasting happiness. Even so this is not to be taken as a categorical condemnation of culture, only unbiblical elements within it.” 
Thus we do not agree, for example, with the Amish of North America, who forbid the use of technology. At the same time, we realise and caution ourselves with the realization that so much of what the world produces is tainted with evil, and must therefore be rejected. In the spheres of culture, science and technology, all things must be tested against the touchstone of Holy Scripture to see what is good and what is evil, what is acceptable and what is not.
…but it demands us to be in the world
The command “‘Come out from among them and be separate, says the Lord…’” (cf. 2 Cor 6:17) is not intended to take us out of the world, in the manner of some Anabaptist sects, such as the Amish or the Hutterites who live in their own communes, having extremely little contact with the world. Christ explicitly indicated this when He prayed to His Father: “I do not pray that You should take them out of the world, but that You should keep them from the evil one” (John 17:15). If we take ourselves out of this world, then how can we shine as lights in it? Then how can we let our good works be seen by men, which induce men to praise God? Then how can we be salt in our community? (cf. Matt 5:14-16).  Then how can we preach on the housetops that which we hear proclaimed in church? Then how can we profess Christ’s name in the world if we take ourselves out of the world? (cf. Matt 10:32).  How can we engage the world in battle if we will not encounter the world? How can we wield the sword of the Spirit, which is the Word of God, and pierce men’s heart and bring them to the conviction that they must repent of their sin and believe in the Lord Jesus Christ if we take ourselves out of the world?
It is God’s intent that we remain in this world. Though we may never become a part of this world, and never form friendships with the people of this world, we must nevertheless live and work, prophesy and shine in this world.
Aren’t we commanded to love our neighbour?
But doesn’t this enmity or hostility of Genesis 3:15 which God has appointed between the citizens of the kingdom of heaven and the people of the world conflict with the command, “You shall love your neighbour as yourself”? How can be at enmity with the world and still love our neighbour? Don’t these necessarily contradict each other?
Furthermore, if we are to win our neighbour for Christ, don’t we have to establish friendships with them? Doesn’t the concept of hostility and war make our prophetic witness to the world ineffective toward the world?
These are honest questions. A young citizen of the kingdom of heaven and a young person of the world might be mutually attracted together. Shouldn’t the young Christian form a friendship with the other in order to win this other for Christ? Couldn’t a woman of the church justify forming a friendship with a neighbouring woman of the world with the hope and intent of winning this woman for Christ? Isn’t forming friendships with the enemy a good way to win them over? But clearly this is against the will of God, as we saw earlier from James 4:4.
How, then, do we reconcile the seemingly contradictory concepts: maintaining enmity or hostility with the world and at the same time loving our neighbour?
In reality, there is no contradiction at all. We mentioned earlier that the hostility which God has established and which we must maintain has the objective to conquer, rather than to destroy. Let me repeat a paragraph which I wrote earlier.
God’s intent in appointing this hostility and in sending Christ to make war against the world is not simply to destroy the world. He came first of all to save. But salvation comes by conquering—conquering the lie by the truth, conquering hatred with love, conquering evil with good, conquering rebellion against God with obedience to God. This is why Christ is portrayed as the conquering king who goes out to battle armed with a sharp two-edged sword that issues from His mouth (cf. Rev 1:16; 2:16). His weapon is the sword of the Spirit, which is the Word that cuts both to salvation and condemnation. By means of the Word, empowered by the Spirit, the minds of men are powerfully though pleasantly enlightened and their hearts renewed. They see the evil character of their ruler, Satan. They see the misery of being dominated by Him. They see the destruction that awaits his realm. At the same time they see the goodness of God. They see the blessedness that comes from submitting to God. They see that the victory ultimately belongs to God. The result is that men of the world cross the battle line. They abandon their allegiance to Satan, renounce their citizenship in the world. They defect to the kingdom of heaven, and rally behind Christ their King. By means of the Word empowered by the Spirit Christ delivers all those whom the Father has given him from the power of darkness and conveys theminto His kingdom (cf. Col 1:13).
It is through our warfare against our neighbour, wielding the sword of the Spirit, that this enemy of God is conquered and brought captive to Christ. We fight against the lie that he embraces, and we show him the truth through the Scriptures. We fight against the corrupt desires that he expresses, and the evil deeds he does, and show him from the Scriptures what is truly noble and good. With the sword of the Spirit we seek to pierce his conscience, his heart, and bring him to his knees before God in repentance and faith. Through our warfare we show our love for our neighbour.
Genesis 3:15 again
Let me conclude by repeating what I said at the start. In Genesis 3:15 God says, “I will put enmity…”. This hostility is appointed by God. God wants this enmity to exist between the two seeds, the children of Satan and the children of God. He who removes this enmity, this hostility, acts contrary to the will of God. Furthermore, this hostility is good. It prevents our assimilation into the world. It also prompts us to fight the good fight against evil, to conquer the worldly and, if it pleases God, to bring them captive to Christ.
This is the 21 March 2005 version – Arthur van Delden.
 In Hebrew word (this program doesn’t have Hebrew symbols – ed.) translated as enmity is translated as hostility in Strong’s; hostility in Brown, Driver, Briggs; hostile disposition in Holladay and Koehler and Baumgartner. The Hebrew word for enemy is derived from the same root.
 1 John 4:8 He who does not love does not know God, for God is love….16 And we have known and believed the love that God has for us. God is love, and he who abides in love abides in God, and God in him.
 Numbers 35:21 “or in enmity he strikes him with his hand so that he dies, the one who struck him shall surely be put to death. He is a murderer. The avenger of blood shall put the murderer to death when he meets him. 22 ‘ However, if he pushes him suddenly without enmity, or throws anything at him without lying in wait….”
 Ezekiel 25:15 ‘ Thus says the Lord GOD: “Because the Philistines dealt vengefully and took vengeance with a spiteful heart, to destroy because of the old hostility,”
 Ezekiel 35:5 “Because you have had an ancient hostility, and have shed the blood of the children of Israel by the power of the sword at the time of their calamity, when their iniquity came to an end….”
 1 John 3:10 In this the children of God and the children of the devil are manifest: Whoever does not practice righteousness is not of God, nor is he who does not love his brother.
 John 8:44 “You are of your father the devil, and the desires of your father you want to do. He was a murderer from the beginning, and does not stand in the truth, because there is no truth in him. When he speaks a lie, he speaks from his own resources, for he is a liar and the father of it.
 1 John 3:10 In this the children of God and the children of the devil are manifest: Whoever does not practice righteousness is not of God, nor is he who does not love his brother.
 John 12:31 “Now is the judgment of this world; now the ruler of this world will be cast out. John 14:30 “I will no longer talk much with you, for the ruler of this world is coming, and he has nothing in Me.
 Ephesians 6:12 For we do not wrestle against flesh and blood, but against principalities, against powers, against the rulers of the darkness of this age, against spiritual hosts of wickedness in the heavenly places.Various Greek lexicons translate the word ‘ruler’ as ‘world-ruler’ (Louw-Nida and Bauer, Arndt & Gingrich) or ‘lord of the world’ (Liddell & Scott);
 1 Corinthians 15:24 Then comes the end, when He delivers the kingdom to God the Father, when He puts an end to all rule and all authority and power. See Ephesians 6:12 in previous note.
 See footnote 9 for John 12:31 and 14:30. John 16:11 “[The Spirit will convict the world] …of judgment, because the ruler of this world is judged.
 1 John 5:19 We know that we are of God, and the whole world lies under the sway of the wicked one.
 John 18:36 Jesus answered, “My kingdom is not of this world. If My kingdom were of this world, My servants would fight, so that I should not be delivered to the Jews; but now My kingdom is not from here.”
 Ephesians 6:11 Put on the whole armor of God, that you may be able to stand against the wiles of the devil. 12 For we do not wrestle against flesh and blood, but against principalities, against powers, against the rulers of the darkness of this age, against spiritual hosts of wickedness in the heavenly places. 13 Therefore take up the whole armor of God, that you may be able to withstand in the evil day, and having done all, to stand. 14 Stand therefore, having girded your waist with truth, having put on the breastplate of righteousness, 15 and having shod your feet with the preparation of the gospel of peace; 16 above all, taking the shield of faith with which you will be able to quench all the fiery darts of the wicked one. 17 And take the helmet of salvation, and the sword of the Spirit, which is the word of God;
 Revelation 6:2 And I looked, and behold, a white horse. He who sat on it had a bow; and a crown was given to him, and he went out conquering and to conquer.
 Revelation 11:7 When they finish their testimony, the beast that ascends out of the bottomless pit will make war against them, overcome them, and kill them.
 Colossians 1:13 He has delivered us from the power of darkness and conveyed us into the kingdom of the Son of His love,
 Revelation 16:16 And they gathered them together to the place called in Hebrew, Armageddon.
 John 16:33 “These things I have spoken to you, that in Me you may have peace. In the world you will have tribulation; but be of good cheer, I have overcome the world.” 1 John 5:4 For whatever is born of God overcomes the world. And this is the victory that has overcome the world — our faith. Revelation 12:10 Then I heard a loud voice saying in heaven, “Now salvation, and strength, and the kingdom of our God, and the power of His Christ have come, for the accuser of our brethren, who accused them before our God day and night, has been cast down.
 William Hendriksen, More than Conquerors, Baker, 1940, p. 168.
 Romans 12:2 And do not be conformed to this world, but be transformed by the renewing of your mind, that you may prove what is that good and acceptable and perfect will of God.
 2 Corinthians 3:18 But we all, with unveiled face, beholding as in a mirror the glory of the Lord, are being transformed into the same image from glory to glory, just as by the Spirit of the Lord.
 1 Peter 2:11 Beloved, I beg you as sojourners and pilgrims, abstain from fleshly lusts which war against the soul,
 The word “world” often refers to “the people of the world” (cf. John 7:7 “The world cannot hate you, but it hates Me because I testify of it that its works are evil”; John 14:17 “the Spirit of truth, whom the world cannot receive, because it neither sees Him nor knows Him”; John 15:18,19 ” If the world hates you, you know that it hated Me before it hated you. If you were of the world, the world would love its own. Yet because you are not of the world, but I chose you out of the world, therefore the world hates you”; John 17:14 “I have given them Your word; and the world has hated them because they are not of the world, just as I am not of the world”; John 17:25 “O righteous Father! The world has not known You, but I have known You; 1 Corinthians 1:21 “For since, in the wisdom of God, the world through wisdom did not know God”; 2 Corinthians 7:10 “…the sorrow of the world produces death”; cf. also Col 2:8, 1 John 3:1,13; 4:5 et. al.
 One of the godless sons of Lamech is said to be “the father of all those who play the harp and flute” (Genesis 4:21) yet these same instruments were used by the Levitical priests in making music of praise in the temple service.
 John Majujina, Measuring the Music, Another Look at the Contemporary Christian Music Debate,” Old Path Publications 2002, p. 17-19
 Matthew 5:14 “You are the light of the world. A city that is set on a hill cannot be hidden. 15 “Nor do they light a lamp and put it under a basket, but on a lampstand, and it gives light to all who are in the house. 16 “Let your light so shine before men, that they may see your good works and glorify your Father in heaven.
 Matthew 10:27 “Whatever I tell you in the dark, speak in the light; and what you hear in the ear, preach on the housetops.” Matthew 10:32 “ Therefore whoever confesses Me before men, him I will also confess before My Father who is in heaven.”