Like all things human, the conscience can fail and encounter illusions and errors. It is a delicate voice that can be overpowered by a noisy, distracted way of life, or almost suffocated by a long-lasting and serious habit of sin.Conscience needs to be nurtured and educated, and the preferred way to form it—at least for those who have the grace of faith—is to relate it to the biblical revelation and the moral law, authoritatively interpreted with the help of the Church and the Holy Spirit.
--Pope John Paul II
