The Gospel reports many incidents when Jesus was accused of violating the sabbath law. But Jesus never fails to respect the holiness of this day. He gives this law its authentic and authoritative interpretation: "The sabbath was made for man, not man for the sabbath." With compassion, Christ declares the sabbath for doing good rather than harm, for saving life rather than killing. The sabbath is the day of the Lord of mercies and a day to honor God. "The Son of Man is lord even of the sabbath."
Source: Catechism of the Catholic Church (Vatican.va)