Our children have so-called “baby-teeth” which fall out by themselves, and in their place other teeth grow — real ones. In the same way we have a heart. But this is a coarse, carnal heart — a selfish one. With such a heart you cannot enter Eternal Life. And it will not fall out by itself. We have to cast it out and replace it with a new heart — not ours, but Christ’s. And any time we help our neighbor (selflessly) and make an effort, we are as if tearing off a piece of our heart and giving it away to our neighbor. And in place of this piece of carnal, sinful heart, the Lord puts in us a similar piece of His heart — Christ’s heart.
—Archbishop Andrei of Novo-Diveyevo