It is possible for truth to be both objective and not provable empirically.

Though it may be wise to be guarded when facing "circular reasoning", circular reasoning is not proof that a conclusion is false.

It is possible for the religious to be sufficiently convinced of the rightness of their truth to live accordingly, while still living peacably with those they believe have a wrong belief system. To live peacably does not mean we must accept all beliefs as equally objectively lacking.