That's the commandment the Supreme Court needs to follow. Taken together, their two 10 commandments decisions are simply incoherent. Read them for yourselves if you have the patience. Kentucky case here; Texas case here. The position of the Court seems to be that the Texas commandments can stand because the Texans didn't really mean anything by them, whereas in Kentucky, since they believe in the 10 Commandments, they must come down.
This is very helpful. Now, before we can know how if our displays in public buildings are constitutional, we have to read the minds of those doing the installations. Or maybe it means federal judges may only post on the walls of their courtrooms words they don't believe in. Call it the hypocrisy clause of the Consitution.
God save this honorable court.