“The law of God is in his heart, and his steps shall not be tripped” (Ps. 36:31). When a man places the Law of God and the holy commandments of God in his heart, so to speak, and loves them, then he comes to hate sin; he becomes inflamed with a desire for life in the Lord, and he restrains himself from every sin.

Venerable Nikon of Optina
Living without Hypocrisy