The religious mantra seems to say that people should not play god using scientific instruments in laboratories. Its perfectly fine to take an active hand in evolution by selective breeding through marriage, thus "remove "bad" genes from a family tree and potentially adding "good" ones.
I would say even that may be somewhat controversial in some circles. One way of playing god almost nobody will argue with is selective breeding of crops and livestock, a practice that has been well established for millenia.
This is funny because it demonstrates a truly child-like understanding of genetics and the reproductive process, as well as expressing some sort of freudian longing to be a woman perhaps? Why not say something equally dumb, "Men are penis-havers in a way women can never be."
For the sentence about prayer, he may have meant, that those people might also consider using of modern medicine a form of playing god. Because prayer could have cured the illness.
