Pagan cannot believe that he is actually agreeing to devote his life to God, to accept life in a monastery. This is a lifestyle that he despises, possibly fears, and also one that he fled from when he was a boy.
But Pagan discovers that beneath the veneer of respectability, piety and humility lies a complex tangle made up of lies, deceit and greed. Pagan may not be the most honest person in the world, but this kind of dirty hypocrisy upsets him enough that he will not stop seeking out the truth even when his very life is threatened. It would seem that someone very high up in the monastic hierarchy guides the conspiracy, and Pagan needs to be wary of what he says and does.