You’re splitting hairs.
Yes, the phrase separation of church and state is not present, but clearly the spirit of that phrase appears in the very First Amendment you quoted, as well as the Constitutional ban on “relgious tests” for determining worthiness for public office.
In the words of Thomas Jefferson:
Believing with you that religion is a matter which lies solely between man & his god, that he owes account to none other for his faith or his worship, that the legitimate powers of government reach actions only, and not opinions, I contemplate with sovereign reverence that act of the whole American people which declared that their legislature should make no law respecting an establishment of religion, or prohibiting the free exercise thereof, thus building a wall of separation between church and state.
The separation of church and state is implied by the Constitution, and this is not, IMHO, a bad thing. It’s not ideal, perhaps, but at least it guarantees (theoritically) that Uncle Sam can’t make Catholicism illegal.
Furthermore, we’ve got a fairly conservative Supreme Court right now, with a Catholic Chief Justice (nb: I make no claims about the quality of his faith or the state of his soul). If Congress attempts to pass a law that outlaws religious teachings about the evils of homosexuality (or any sinful lifestyle), I have difficulty believing it would stand up under scrutiny.
By the way, I have heard of no such law…anyone have a source on that?