Michael was right when he described the moral and religious nature of the issue thusly:

When some Leftist teachers espouse a very specific religious belief, namely that it's totally morally acceptable for men and men to be the same as men and women, or that men can become women and women can become men, that's a religious belief. It's called Gnostic Dualism, among other things.

When his guest disagreed that the issue is religious in nature (demonstrating his own lack of understanding of the term, I would suggest), Michael was spot on when he challenged his guest with this:

By definition it's religious. You're talking about the nature of morality. You're talking about the nature of humanity. You're talking about the relationship between our soul and our body. How much more religious can you get?

In response, Michael's guest then further demonstrated his own ignorance of religious matters when he said, "It's not [religious] because it's not part of a catechism, for example, from a church."

Wrong. There are a number of historic Christian catechisms that touch on all the issues that Michael mentioned, not to mention specifically describing marriage as between a man and a woman, as our religious text -- the Bible -- demands. But he is also wrong in demanding that such things be found explicitly stated in a catechism in the first place, in order to be considered a part of a religious belief system. He fails to understand that doctrinal statements and catechisms are by their very nature summaries of a system of belief found in the Bible. Thus, sticking with the Christian example that they were both discussing, the Bible itself is the source document that constitutes the basis for our faith, and it clearly deals with these issues. I should also mention that there are voluminous amounts of Christian theological literature which discuss the teaching of the Bible on these subjects. At any rate, the guy doesn't really seem to understand what he is talking about.