In Romans 1:18-32, Paul identifies the pattern by which humanity (and particular civilizations within humanity) slide into apostasy and damnation.
The sequence is ingratitude, leading to idolatry, leading to immorality. We refuse to thank and glorify the God who made us, turning to idols instead; the outworking of this idolatry is manifested in various forms of dehumanizing wickedness, most especially homosexuality.
Paul identifies three exchanges that take place as part of this process:
1. Claiming to be wise, they became fools, exchanging the glory of God for creaturely idols.
2. They exchanged the truth of God for a lie and worshipped and served the creature rather than the Creator.
3. Their women exchanged natural relations for those contrary to nature (that is, lesbianism), and likewise men gave up natural relations with women and were consumed with the vile passions of same-sex attraction (homosexuality).
All three of these exchanges are rooted in the fall of Adam and Eve. Romans 1 is full of echoes of Genesis 3, including the three exchanges:
1. Eve thought the forbidden fruit was able to make her wise so she became a fool. She exchanged true wisdom for folly.
2. In believing the serpent's deception, Eve exchanged the truth of God's command for the lie of the serpent, and thus worshipped and served the creature (Satan) rather than God.
3. In submitting to the serpent, Eve committed spiritual adultery with Satan. While the fall did not include an act of homosexuality, it did include an act of sex-role exchange, which is homosexuality in seed form. Instead of the woman following the lead of Adam as her pastor and husband, he passively and effeminately followed her and received the sacramental meal from her hands. There is a sexual role reversal.
The purpose of the gospel is to reverse these three exchanges. Through the work of Christ and the Spirit, we are restored:
1. We exchange the pseudo-glory of idols for the true glory of the living God, and thus turn from foolishness to wisdom. We give God thanks and honor him. Thanking God is the key to wisdom and a restored life; in other words, the Eucharistic meal (where we give thanks over the bread and wine) reverses the pattern of the fall.
2. We exchange the lies of Satan (and false religions, worldviews, ideologies, etc.) for the truth of God's Word. We worship the God who made us, according to his design, rejecting autonomy and submitting to his law.
3. We exchange the unnatural use of our bodies and sexuality for their natural use in male-female marriage, producing fruitfulness and life rather than death. Marital love and romance replace vile passions; the men have affection for their brides once again. The original patriarchal order of male headship is restored.