This quote shows how Prince Hamlet feels towards his uncle after the ghost Old Hamlet tells him that it was his brother that poisoned him and caused his death. Prince Hamlet promised his father that he will avenge his death.
Better be slapped with the truth than kissed with a lie! And the truth is: the Novus Ordo Sect IS NOT THE CATHOLIC CHURCH! It's better to be outside than to be an accomplice of their heresies and misdeeds!