Conscience is a personal, reasoned, practical judgment that something is right or wrong; that is, whether something is in accordance with the will and law of God, which is written within one’s soul.
Conscience makes us aware of what God wants us to do at a given time. Furthermore, it helps us to know when we have sinned. Conscience tells us whether an action is right or wrong and whether it is a mortal or a venial sin. Our conscience is our mind’s ability to judge moral matters. It is important to note, however, that for most people, reason alone is not a sufficient guide in moral matters. The conscience must be instructed and formed. We must learn from Christ as He speaks to us in the hidden recesses of our souls, and as He teaches us through His Catholic Church.