The Westminster Shorter Catechism
Q. 57. Which is the fourth commandment?
A. The fourth commandment is, Remember the Sabbath day, to keep it holy. Six days shalt thou 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, thy man-servant, nor thy maid-servant, nor thy cattle, nor thy stranger that is within thy gates: for in six days the Lord made heaven and earth, the sea, and all that in them is, and rested the seventh day: wherefore the Lord blessed the sabbath day and hallowed it.
Q. 58. What is required in the fourth commandment?
A. The fourth commandment requireth the keeping holy to God such set times as he hath appointed in his Word; expressly one whole day in seven to be a holy Sabbath to himself.
The Westminster Shorter Catechism in Modern English:
Q.57. What is the fourth commandment?
A. The fourth commandment is: Remember the Sabbath day by keeping it holy. Six days shall you labour and do all your work, but the seventh day is a Sabbath to the Lord your God. On it you shall not do any work, neither you, nor your son or daughter, nor your manservant or maidservant, nor your animals, nor the alien within your gates. For in six days the Lord made the heavens and the earth, the sea, and all that is in them, but he rested on the seventh day. Therefore the Lord blessed the Sabbath day and made it holy.
Q. 58. What does the fourth commandment require?
A. The fourth commandment requires us to set apart to God the times He has established in His word - specifically one whole day out of every seven as a holy Sabbath to Him.
1. How does this commandment apply to worship?
This commandment speaks of the time of worship and naturally follows the first three commandments. The first spoke of the object of worship, the second of the means of worship, the third of the manner of worship.
2. How can one decide what times should be kept for public worship?
The only times that are to be kept for public worship are the times appointed in the Word of God. It is not right before God to add other times, or holy days, to the Word.
3. What does the Bible tell us is the time set aside for worship?
The Bible teaches that one whole day (a day of twenty-four hours) is set aside for the worship of the holy God.
4. What is meant by the word "Sabbath"?
The word "Sabbath" is a Hebrew word, signifying "rest", as is taught in Hebrews 4:9.
5. Why does our question call it a "holy Sabbath"?
It is a "holy" Sabbath because it has been consecrated and set apart by God.
6. Is this particular commandment a part of the ceremonial law or the moral law?
This particular commandment is a part of the moral law and is to be kept by all nations and throughout all generations. It has never been annulled. The Lord Jesus Christ gave testimony to it. He is our Lord and He is also "Lord of the Sabbath". (Luke 6:5)