But is it the truth? ------ Ah yes,that is crucial! (John 4:23;17:17) Sincerity alone is insufficient. Saul who later became Paul lamented that many Jews continued zealously pursuing righteousness by works of law rather than faith in Christ(Romans 9:31-10:4). What was lacking? (Romans 10:2) For I bear them witness that they have a zeal for God; but not according to accurate knowledge; An "accurate knowledge" of truth must be coupled with "zeal for God." So its not a question of 'What religion suits me best?' Rather the question should be 'Is my religion solidly based on God's Word of truth?' (2 Timothy 3:16) It needs to be to be acceptable to God.(Romans 12:1,2)