I think I'm figuring out what you might mean when you say "the world". It appears that when you say "world" you mean "non-Christians". And so anything non-Christians like and do is bad, and there can be no overlap between Christianity and what non-Christians believe, think, and do.
Am I correct? Close?
The problem is that this isn't the Bible means when it speaks of "the world" in its negative sense. The negative sense of "the world" refers to the "cosmic architecture" of the way things are post-Fall, the present arrangement (the Greek word
kosmos means "arrangement" or "order"). St. Paul, therefore, speaks of how our contest or struggle is not with "flesh and blood", it's not with our fellow human beings, and so the tools at our disposal are not tools of "war" to fight other people, but rather ours is a spiritual toolset of faith, hope, love, truth, and the Gospel to guard ourselves against the cosmic, spiritual forces of darkness.
It is not atheists and agnostics or Jews, Muslims, Buddhists, or (fill in the blank) that we are at contention with; it is with the dark spiritual architecture that governs the present fallen age. The spiritual landscape in which creation, including human beings, are made victims of the tyranny of death and the the impulses of evil that emerge out of our own broken human condition--as creatures made to bear the Divine Image, but instead collaborate with our own self-destruction by giving into the lusts or passions of our flesh. AKA sin. Through sin we collaborate with death, we betray our God-given meaning, we turn the human potential to act justly toward others and all other creatures and instead pervert it into acts of cruelty. The parent has been given the gift of parenthood and thus is called to the beautiful vocation of raising a child, but if a parent gives into anger they abuse the child, the parent may become selfish, callous, or the parental instincts may be bent out of shape by past trauma of their own broken childhood--and so the cycle of abuse continues. All manner of evil is perpetuated in a world that labors under the tyranny of death, especially as we feed our self-orientated instincts and impulses due to our own innate brokenness.
But all of this emerges out of a hurting creation, a creation that St. Paul says groans as though in labor pains, subject to futility--the futility of death. But it is always against the backdrop of dark, spiritual cosmic forces that this happens. And so it is not with human beings made in God's Image that we bear "weapons", but against the spiritual forces of darkness--which is why our armor and our weapons are spiritual--love, truth, kindness, and
Good News.
So when we read that the one who is friends with the world is an enemy of God, it does not mean finding common ground with other people outside of our religion; it means the love and affection for a system of darkness that is imposing and cruel--that which gives license to the passions to act unjustly against others. "The world" is that which says "take what you want, and care about none who suffer" it is might makes right, it is strength above weakness, it is the first is first, what's mine is mine, and what's yours is mine.
Jesus comes with a world-shattering proclamation: "The kingdom of God is at hand, repent and believe the Good News" and then goes on over the course of His entire earthly ministry to define what that means through every word He spoke, and every act He did. It's Jesus amid the prostitutes, the tax collectors, the lepers; it's feeding the five thousand, it's saying to the paralytic man, "Your sins are forgiven" and "Get up and walk". It's saying to the woman caught in adultery, "Neither do I condemn you, go and sin no more". It's "the first shall be last and the last shall be first" and "the greatest among you is your slave". It's "Blessed are the poor, for theirs is God's kingdom" and "Woe to you who are rich".
It's that the means of Divine victory does not come with raising and leading an army and going to Rome to overthrow Caesar; but the Cross where the Lamb of God is slain, and who says, "Father forgive them, they don't know what they're doing".
It is weakness over strength. It is smallness over bigness. It is leastness over greatness. It is "the prostitutes and tax collectors are entering the kingdom ahead of you". It's that in a feeding trough, on a cool winter's night outside of Bethlehem, a tiny Baby was wrapped in meager swaddling, cradles by a mild virgin mother, and an unimportant carpenter as her fiance. Surrounded by the royal powers of Herod, the aristocratic powers and structures of the Sadducees over the Temple, and men like Pontius Pilate ruling Judea as the representative of a foreign tyrant. But this Infant was not born to seize Herod's crown or throw Caesar off his distant throne; but to proclaim a new kind of kingdom, the eternal kingdom, because God is King--and how is God King? He looks like that Infant in a feeding trough, visited by shepherds; He looks like the Boy playing in Joseph's carpenter's shop, and who has peculiar conversations with the theologians and teachers of the day in the Temple. It looks like an unassuming Man, traveling around Galilee, and also Judea saying and doing things which confused and angered those with power because they benefit from the present way of how things work. Reminding everyone of the ancient promises of YHWH, and speaking of the fulfillment of those ancient promises. Not through pomp and splendor, not through a military parade, not by conquest; but by the simpleness of His Person, by the gentleness of His hands toward the least, by His time spent with the unimportant, and by His entrance on the back of a donkey--toward the unglorious, shameful cross of death.
So that He might take the powers and principalities and make a spectacle of them, He is above them not because He had a greater show of force, but because His Life was His to lay down which He chose to do; and death could not destroy Him. For all the dark powers, death, the devil, sin, the monstrous legions of violence that permeate this present reality of ours--in the end could not best Him. For on a Sunday morning, when all was still, the stone was rolled away.
He took on hell, and hell lost.
The world hated Him. Why? Because He was a jerk who used religion and pious words to insult the people He thought were beneath Him? No, that's what the hypocritical religious elite did--they snubbed their noses at the lesser people while patting themselves on the back for being more righteous, more pious, more religious, more moral than all of them. They would not dare to pal with a Greek dog or a filthy harlot; they would not deign to visit a leper or console a poor man with a dying child.
It hated Him because the world hates it when a starving child is fed, and when a wretched man is shown compassion. The world hates it when a wicked man is forgiven and has the opportunity to change his ways. The world hates it when the rich are shown to be thieves of the wealth that belongs to the poor; the world hates it when the mighty are shown to be naked and meaningless because they have been given the gifts to care for those who can't care for themselves and do nothing but profit for themselves--and are called out for it. The world hates it when it is shown that they have been nagging on and on about the speck in someone else's eye, all the while a cedar is growing out of theirs. It hates that "those people" are shown dignity and compassion. It hates to be challenged, it hates to feel uncomfortable. It loves it when a man like Caesar is lord, it loves it when a man like Herod wears the crown, it loves it when Caiaphas in in charge of the Temple, and it loves it when hypocrites rule the synagogues. The world loves those who flaunt and who brag. The world loves power and wealth and greed and violence. The world loves it when a tyrant is in charge, and when the laws are corrupt and unjust and benefit those at the top. The world adores war, and the clashing of nations, tribes, and kingdoms in bitter endless conflict as each side tells itself that they are right and the other side is evil. The world loves it when brothers quarrel, and sisters fight; it adores when parents abuse their children, and children rebel against their parents. The world loves holding men in chains, and forcing women to be objects of desire. The world loves division and conquest--finding all the petty differences among the common and universal human creature and drawing lines on maps, arguing who has the better skin color, and whose language is sophisticated and the other barbaric. It loves saying "men over there" and "women over there"; it loves belittling the different and glorying in the homogenous.
That's the world.
-CryptoLutheran