Q 116 What is required in the fourth commandment?

A. The fourth commandment requireth of all men the sanctifying or keeping holy to God such set times as he hath appointed in his Word, expressly one whole day in seven; which was the seventh from the beginning of the world to the resurrection of Christ, and the first day of the week ever since, and so to continue to the end of the world; which is the Christian sabbath,[622] and in the New Testament called The Lord’s day.[623]

[622] Deuteronomy 5:12-14. Keep the sabbath day to sanctify it, as the LORD thy God hath commanded thee. Six days thou shalt labour, and do all thy work: But the seventh day is the sabbath of the LORD thy God: in it thou shalt not do any work, thou, nor thy son, nor thy daughter, nor thy manservant, nor thy maidservant, nor thine ox, nor thine donkey, nor any of thy cattle, nor thy stranger that is within thy gates; that thy manservant and thy maidservant may rest as well as thou.

Genesis 2:2-3. And on the seventh day God ended his work which he had made; and he rested on the seventh day from all his work which he had made. And God blessed the seventh day, and sanctified it: because that in it he had rested from all his work which God created and made.

1 Corinthians 16:1-2. Now concerning the collection for the saints, as I have given order to the churches of Galatia, even so do ye. Upon the first day of the week let every one of you lay by him in store, as God hath prospered him, that there be no gatherings when I come.

Matthew 5:17-18. Think not that I am come to destroy the law, or the prophets: I am not come to destroy, but to fulfil. For verily I say unto you, Till heaven and earth pass, one jot or one tittle shall in no wise pass from the law, till all be fulfilled.

Isaiah 56:2, 4, 6-7. Blessed is the man that doeth this, and the son of man that layeth hold on it; that keepeth the sabbath from polluting it, and keepeth his hand from doing any evil.... For thus saith the LORD unto the eunuchs that keep my sabbaths, and choose the things that please me, and take hold of my covenant.... Also the sons of the stranger, that join themselves to the LORD, to serve him, and to love the name of the LORD, to be his servants, every one that keepeth the sabbath from polluting it, and taketh hold of my covenant; Even them will I bring to my holy mountain, and make them joyful in my house of prayer: their burnt offerings and their sacrifices shall be accepted upon mine altar; for mine house shall be called an house of prayer for all people.

[623] Revelation 1:10. I was in the Spirit on the Lord's day, and heard behind me a great voice, as of a trumpet.