‘And even as they did not think it worthwhile to have God in their knowledge, God gave them up to an unfit mind, to do those things which are not fitting,'
Not only did mankind ‘know God' but refuse to own His worth (Romans 1:21), turning instead to idols (Romans 1:23), they also considered that to keep the true God in their knowledge (epignosis - spiritual knowledge) at all was not worthwhile. Thus they not only blasphemed against Him with their false worship (Romans 1:21-23), but also despised Him at the same time, by forgetting Him in their daily lives. As a result God once again ‘gave them up' to the consequences of their sins, allowing them to develop unfit minds, minds which would be rejected after testing (adokimos). Note the play on the words dokimazo (did not approve, think it worthwhile) and adokimos (disapproved, rejected after testing). They did not approve and so, having tested them, He did not approve them.
The verb dokimazo means ‘to approve, to regard as worthy, to think of as worthwhile'. Thus they did not ‘approve' of having God in their knowledge, which was why God did not ‘approve' of them. The choice is open to us all. Either we retain God in our knowledge and commit ourselves to His ways, or we put Him out of our minds and are given up by Him to unfitness and disapproval. We cannot be neutral.
And the end result of God's disapproval was that their minds became unfit, and they began to do what was not fitting. Not all followed the way of sexual perversion. But all became involved in at least one of the sins in the long catalogue of sins that follows. Many a person has come to the crossroads where they had to choose whether they wanted to retain God in their knowledge or not, and having rejected the opportunity have sunk into deep sin. Judas is the prime example.