The fourth commandment begins with this positive requirement: “Remember the Sabbath day, to keep it holy” (Ex. 20:8). You ought to sanctify the Sabbath—you ought to set it aside for the purposes of God. What are God’s purposes for the Sabbath?

The Sabbath reminds you that God is your Creator. “For in six days the Lord made the heavens and the earth, the sea and all that is in them” (Ex. 20:11). The Sabbath also reminds you that God is your redeemer. “You shall remember that you were a slave in the land of Egypt, and the Lord your God brought you out of there by a mighty hand and by an outstretched arm” (Deut. 5:15). Israel’s redemption foreshadows yours (1 Cor. 5:7). You belong to God by right of creation and redemption.

The fourth commandment indicates how you ought to remember, or memorialize, your creation and redemption. “Six days you shall labor and do all your work, but the seventh day is a Sabbath of the Lord your God; in it you shall not do any work” (Ex. 20:9-10). The Sabbath is therefore a day of rest (Ex. 31:15; Deut. 5:14). At the same time, the Sabbath is a sign. “You shall surely observe My sabbaths; for this is a sign between Me and you throughout your generations” (Ex. 31:13). As a sign what does it signify?

Ultimately, “rest” is a state of grace which leads into heavenly rest. Hebrews 4:1-3 exhorts, “Let us fear if, while a promise remains of entering His rest, any one of you may seem to have come short of it. For indeed we have had good news preached to us, just as they also; but the word they heard did not profit them, because it was not united by faith in those who heard. For we who have believed enter that rest.” You enter rest with God when you abandon your own works and trust in Jesus Christ as the only adequate payment for your sins. You enter rest by grace through faith.

And so, how do you remember your redemption? You stop your regular work and recreation to rest on the Sabbath Day. You assemble with God’s people, enter God’s gracious presence for worship, and taste the things of heaven. When you cease your work and taste God’s heaven, you testify to a watching world that your salvation is by grace through faith and not by works. You testify that you trust the works of your Creator and Redeemer, and not your own, to give you right standing with Him. You testify that you are not your own, “you have been bought with a price” (1 Cor. 6:20). You memorialize God’s justifying grace in your life by ceasing to work as though eternal life depends upon it.

There is another purpose for the Sabbath. Consider again Exodus 31:13: “You shall surely observe My sabbaths; for this is a sign between Me and you throughout your generations, that you may know that I am the Lord who sanctifies you” (italics added). God promises to use the Sabbath Day as a means to assure you that you belong to Him. You may know that you trust Christ for salvation but may lack deeper assurance of salvation itself. You are therefore tempted to abandon Sabbath observance and worship. This is the exact opposite of what you should do. The Sabbath Day is God’s means to remind you and assure you that you belong to Him by right of creation and redemption.