Sin is transgression – resisting, living at cross-purposes with God's ways.
If you are enjoying white-water rapids flowing with the current you can have the thrill of being carried along with the powerful, surging water beneath you. But if you “dig in your heels” locking yourself to a rock or even trying to move cross-wise to the current, you will suddenly find yourself in realization of how intensely powerful and dangerous the water can be if you are not willing to move in synchronization with it.
The last half of Romans 1 is describing this very situation in contrast to the first half describing the very opposite. The identification of each is found in back to back verses 17 and 18 - “the righteousness of God is revealed”, and “the wrath of God is revealed”. Reading all the previous verses before 17 reveals the righteousness of God. Reading the following verses reveals the wrath of God.
But unlike the typical spin that most people assume by projecting their own feelings of wrath onto God's character, what in fact is revealed here is the natural consequences of resisting the powerful current of God's intense passion of love.
Just as trying to stop in the middle of a surging river or even move in a different direction suddenly and dramatically produces life-threatening danger, resistance to the power of God's love and His ways of relating produces life-destroying results. Why then do we blame God/the current for the dangerous consequences of our resistance when we could be enjoying the most exhilarating ride of our lives? In fact, this very penchant to blame God and accuse Him of arbitrarily imposing these “punishments” on those who resist Him in itself will put us in the path of resisting Him. If we chose to continue to blame God for sin's effects we will tragically find ourselves suffering those very effects. And the sad consequence will be that our conclusions will seem to be justified while in fact we are only living under the intense deception of sin and the lies that reinforce it.
Notice what Romans 1 really says about how God's “wrath” is revealed. I notice two important principles emerging here: (1) “they knew God” (v. 21), and (2) “God gave them over”, or released them. These are repeated in various ways throughout the rest of this chapter. What it is saying, to use our current analogy is that (1) they cannot help but notice that there is a strong current underneath their lives and that it is consistently urging them in a particular direction. But when they chose to “exchange” the real for the imitation (v. 23) and refused to “acknowledge God”, then in respect for their choice to resist the current of His love and passion for them God, in the intense anguish of His breaking heart for them “gives them over” to the terrible natural consequences of their stubborn resistance.
Just in case we glibly smile believing that we are safe from that problem, Paul goes on in chapter 2 to point out that when we harbor “judgment” in our hearts against others who are suffering these results of resisting the current we place ourselves in the same situation and will unwittingly find ourselves in the same danger as the ones we condemn.
I want to explore this much more but right now I want to sit in a raft and relish the sun and the spray in my face as the current of God's love surrounds me and carries me through this day.