Not buying it. "No preference in law" means no preference in law. Justice Moore has no authority to pass any laws, or to even administer the laws outside of an actual case or controversy before him in court, therefore his action cannot possibly be considered to partake in any way of the authority of law.
Now, you tell me. If the Alabama Legislature passes the following law, does it pass constitutional muster:
The State of Alabama hereby declares that the Christian God is sovereign over all laws of the State and each citizen of the State, and that this sovereignty shall be recognized by the erection of a large monument in the rotunda of the Judicial Building, to remind all citizens of Alabama and all litigants in its courts that the Christian God is the source of all legal authority in this State. The display of non-Christian or secular sources of law alongside the monument is expressly prohibited.
Well, it would satisfy the first criterion in the prohibition - namely, that it's an actual law - but then it's a dead end from there. Such a law is not granting preference to a particular organization ("sect, society, denomination") nor to a particular mode - that is, method - of worship.
It doesn't really matter if you do. Every court in the land recognizes that a government cannot behave unconstitutionally simply by not passing legislation in support of its unconstitutional acts.