God's treatment of sin lets in a flood of light on the sort of thing it is. Three times over in this summary Paul says that God "gave them up." As they cast out all acknowledgment of God, He gave them up to an outcast mind. When they turned God out-of-doors, God left them indoors to themselves. It was the worst thing He could do, and the best. Worst -- to be left alone with sin. Best, because the sin would get so vile that the man in God's image would want to turn it out, and get God back. Man never turns from sin until he feels its vileness to the sickening point. When things get to the acute stage, and a sharp crisis is on, then as a rule there will be an eager turning to the One who can cleanse and make over new; but usually not until then.

Sin has a terrific gait. Give it a loose rein and man will get winded and ready to drop. Only then is he ready to drop it. Sin can't be patched up or mended. Nursing only helps it to its feet for a fresh start. The whole trouble is in the nature of the thing. The heart pumps the hot blood of rebellion. Its lungs can breathe only self-willed air. The worst punishment of sin is that left alone it breeds more sin, and worse sin. The worst of sin is in its brood. It is very prolific. Every sin is a seed-sin. The breeding process gets the sort more refined in its coarseness.

"This is the very curse of evil deed,
That of new sin it becomes the seed."[2]

And the plain statements of the Book, and the inevitable working of man's nature, reveal all the bad results of sin intensifying indefinitely in the after-life. Jesus is God letting sin do its worst, upon Himself, that man might see its utter, stubborn damnableness, and eagerly turn from it, and back to Him.