Even after children are grown, they still watch and learn from the pattern of their parents. Don't spend all your time pining over past mistakes. If you want your religion to be attractive to your kids, then be as positive and joyful as you can. If you are always acting gloomy and guilty, they will be repelled by your religion. Don't nag, condemn, or criticize.
People generally know when they are doing something wrong, and no one appreciates being reminded.
Some parents preach at their children through prayers in their presence. Give them to God for blessing or trouble. We automatically pray that God will bless and protect our children, that may be the wrong prayer. If God needs to allow trouble to bring them to their knees, then release them to the Lord for whatever He deems best, in order that they might be saved for eternity. Never speak evil of the church or pastor.