What -- they'd rather he lied about the basis for his decisions?
I can tell you that this libertarian would not have preferred that he lied but that he practiced his faith in private (meaning outside of the government). It's inappropriate to use government to advance one's religious beliefs.
The only criteria the president should apply when appointing judges is wether or not the candidates understand the concept of rights and liberty, separation of powers, federalism, state sovereignty, and wether they can read plain English.