Roman Catechism 26.27

Chapter 26 — Part III: The Decalogue — The Third Commandment

Section 27. It is also a sign of a spiritual and celestial sabbath. The spiritual sabbath consists in a holy and mystical rest, wherein the old man being buried with Christ, is renewed to life and carefully applies himself to act in accordance with the spirit of Christian piety. For those who were once darkness but are now light in the Lord, should walk as children of the light, in all goodness and justice and truth, having no fellowship with the unfruitful works of darkness.