How can we know that believers should not love the world?

In 1 John 2:15, the command is unequivocal: 'If anyone loves the world, the love of the Father is not in him.' This teaches that a believer's affection cannot be divided between God and worldly desires. The love of the Father involves a commitment to Spirit-led living and drawing near to God, which inherently rejects the allure of worldly pursuits. The warnings are particularly addressed to believers, identifying that even they can fall prey to worldliness. Hence, the biblical truth is that one's relationship with God is central, and any affection towards the world must be constantly scrutinized in light of our commitment to Christ.