Longer Catechism (Orthodox) 26.537

Chapter 26 — Part III — The Ten Commandments

Section 537. Q. Is the Sabbath kept in the Christian Church? A. It is not kept, strictly speaking, as a holy day; but still in memory of the creation of the world, and in continuation of its original observance, it is distinguished from the other days of the week by a relaxation of the rule for fasting.