The 14th was designed to protect individuals' rights. But only rights that were specifically adumbrated in the prior law and jurisprudence. The first amendment does not give anyone the right to demand the banning of all forms of religion from public life, nor does any provision of the constitution, nor did any court decision preceding the 14th's ratification.
"Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof."
The first clause is a restriction on the powers of the federal government, and has nothing to do with the individual. The latter (and here I disagree with Keyes) is an affirmation of an individual's freedom to practice the faith of his choosing. So, even if you were to apply the 14th to the states, that would actually do nothing to support your belief that Judge Moore should take down his rock.
Neither provision says anything about whether or not some state official can put up a decalogue or not. Really, the issue is quite overblown. Hanging some Ten Commandments on a wall is really a victimless "crime." Nobody's interests are harmed by having them on the wall. 99% of all Alabamians would never even know of their existence.