No, Sunday is not the Sabbath. The Sabbath was a distinctive part of Israel’s program that God gave the chosen nation at Mt. Sinai.
“Thou camest down also upon mount Sinai, and spakest with them from heaven, and gavest them right judgments, and true laws, good statutes and commandments: And madest known unto them thy holy sabbath…” (Neh. 9:13,14).
The Lord instituted the Sabbath as a gift for Israel. The word Sabbath means “rest.” God gave His people Israel a day of rest each week to rejuvenate their bodies and minds. It was to be a time of rest, feasting, and enjoying family. More importantly, He gave it in order to break the day-in, day-out cycle of life, so that Israel would not forget their God and would worship and give thanks to Him on that day.
According to Exodus 20:11, the Hebrews were to cease all work because the Creator “rested” after the sixth day of creation on “the seventh day.” So Israel was to follow the Creator’s example for their week, making the Sabbath a day to commemorate the Lord’s creation of the world and to celebrate His provision.
“Wherefore the children of Israel shall keep the Sabbath, to observe the Sabbath…for a perpetual covenant. It is a sign between Me and the children of Israel for ever: for in six days the Lord made heaven and earth, and on the seventh day He rested” (Ex. 31:16,17).
The Sabbath was a sign, a distinguishing mark, of God’s chosen people. It was “a sign between [God] and…Israel.” The Sabbath was for Israel, and it was given to Israel under the Law.
Today, we are not under the Law, we are under Grace (Rom. 6:14). We are not Israel; we are the Body of Christ (Eph. 1:22,23). The Sabbath is not to be observed under Grace. Paul gives no instruction for the Body of Christ to observe the Sabbath. Instead, he speaks of the Church gathering “upon the first day of the week” (I Cor. 16:2). Sunday is not the Sabbath and should never be called the Sabbath. Doing so confuses what “the first day of the week” signifies under Grace, and what “the seventh day” signified under the Law.
The Sabbath speaks of rest after work and relates to the Law and the work required by those under the Law in Law-keeping, with the works, observation of feasts, and sacrifices that Israel was commanded to do continually by faith. The Sabbath foreshadows the rest that Israel will enjoy in her end times, in her millennial rest within the earthly kingdom.
Sunday worship on the first day of the week speaks to a rest that takes place before work and relates to Grace and the rest we, the Body of Christ, have in Christ and His finished work right up front. Having trusted that Christ died for our sins, was buried, and rose again (I Cor. 15:3,4), we are “complete in [Christ]” (Col. 2:10). Salvation is a “gift” that we receive the moment we believe; it is “not of works” (Eph. 2:8,9). For most working people, our work week follows after the first day of the week. And under Grace, because we are saved, “works” follow after out of joy and gratitude for our accomplished salvation in Christ (Eph. 2:10).
The Sabbath commemorated the Lord’s creation of the world, while our Sunday worship commemorates the Lord’s resurrection each week, who rose again on “the first day of the week” (Luke 24:1). Thus as we meet on Sundays each new week, we do so in worship of our living, risen Savior, and the newness of life we have in Him (Rom. 6:4). source