The Great Canon of Repentance by St. Andrew of Crete, especially when it is read in the Standing of St. Mary – There are many, many troparions. It seems hard to stand, hard to listen! It’s a long service. But you know, when you’re standing, you don’t notice that the canon has passed. 

When the choir sings “Have mercy on me, O God, have mercy on me.” – for every troparion I have to recall a sin I have done. And when for each troparion you recall: “Lord, I have sinned in this”, and for the next troparion – in that, and for the third – in that… your soul begins to revive. And a repentant sigh comes, and tears appear in your dry eyes, and every word of the canon tears your soul!

Metropolitan Arseny of Svyatogorsk