Today is the feast of Holy Mother St. Teresa of Avila.
My favorite quote from her is, "Prayer is the trap door out of sin."
So many times people are told that if they are in a state of mortal sin they cannot merit any grace and their prayers and good works are not efficacious.
Nevertheless, it is important that the sinner should pray, pray as best as he knows how and as often as he can - even when he feels he cannot quit his sins. God never fails to hear prayer, especially the prayer to be free of one's sins, placing all of one's confidence in the mercy of God - one doesn't have to be perfect to pray. The idea of merit? Leave that to the Blood of Christ.
Pray, pray, pray without ceasing, this is how you will attain eternal life.
St. Teresa, teach us to pray.