Are you being intentionally obtuse? I'm failing to discuss the issue at hand, because I am categorically rejecting your premise that anyone here thinks "it's acceptable for a judge to rely solely on his religious beliefs to interpret the constitution [sic] or the law." One of the things that seems to have escaped your notice is the distinction between an activist justice, and an originalist justice.
Judicial activism is illegitimate on its face, so the notion that a Catholic judicial activist is somehow scarier than a secular judicial activist is to use bigotry to distract from the fact that judicial activism is the crime, not why the activism was perpetrated.
If a justice's Catholicism is demanding Roe v. Wade be struck down, it is not because abortion is a heinous crime against humanity, but because the legal underpinning is totally without merit and constitutes a limited judicial coup d'etat on the Constitution. There are legitimate means for changing the Constitution, and fiat rulings by justices with inferiority complexes isn't one of them.
There.... now was that so hard?
It turns out we agree. Judicial activism is unacceptable.