God created us and redeemed us so we can have life in abundance — not just in Heaven, but even now, on earth. By His providence, He calls all people to experience perfect happiness and, through His Church, He gives us the guidance we need to get there. Catholic moral theology is that guidance. Far from negating what is authentically human, it radically affirms all that is good and true. To study moral theology is to discover who we are and for what we are made. It is an encounter with the God who loves us, and it is an essential part of our quest for meaning, fulfillment, and happiness.

The Ten Commandments form the moral heart of the Old Law. As an expression of the natural law, they continue to guide us today. They showed Israel how they should relate to both God (in the First through Third Commandments) and their neighbor (in the Fourth through Tenth Commandments). In revealing this to Israel, the Ten Commandments showed them how they could be truly free.

The Old Covenant was the first part of God’s plan. Jesus’ coming began the second part. Because of the unity of God’s plan, Jesus does not abolish all the laws that had come before Him. Rather, as He explains, “Do not think that I have come to abolish the law or the prophets. I have come not to abolish but to fulfill” (Matt. 5:17). Jesus, however, does more than simply fulfill and endorse the Ten Commandments; He perfects them. He does this by calling us to live them within as well as without, asking us to let the Commandments shape our hearts as well as our acts. To make that possible, He also supplies us with the grace we need to keep the Commandments, making us able to live the law in a way that was not possible before His coming.

In our lives, we make choices that either lead us on the path toward Heaven or the path of slavery and death in sin. God does give us the freedom to choose between them, to choose to love Him or to sin. In order for our choices between good and evil to mean something — for them to be moral choices — we must be free in our choice. Free will is a gift from God Himself and is a faculty or ability of the soul. God respects our dignity by allowing us to be in control of our actions and responsible for our choices. God wrote His law within the heart of every single human person. This gift of His law is called a conscience. Our conscience, however, does not work like magic. It does not tell us the difference between right or wrong with no effort on our part. Forming our conscience so we can make good moral choices takes a lot of training and study.

Because God created us, He knows what is good for us. We find our ultimate happiness growing in holiness to become closer to Him. We find true freedom growing in truth and goodness because that ultimately fulfills our human nature, making us freer to be who we are meant to be. God knows that choosing the good is not always easy for us. He knows we are attracted to sin and the right choices are not always clear. So, to help us, God gives us grace, virtue, the Sacraments, and a host of other means to help us remain on the path of holiness.