

Introduction:
As a believer in God and his Son, the Lord Jesus Christ, I feel that we as Christians need to know the following truth. We at my home have been keeping the Sabbath for a few years now. No place in God’s Word did I see where the Sabbath was changed to Sunday.
Even Jesus told his people to keep His Commandments. He did not say all but the 4th one.
This post tells how it was changed to Sunday which in ancient times was for sun worshipers and who thought they were greater than God and had the authority to change the day.
Table of Contents:
Second Century
Fourth Century
The Change of the Sabbath
Second Century
The Sabbath change from Saturday to Sunday was a slow process that began before A.D. 150 and continued for three centuries. Before the Jewish revolt under Bar Cocheba, A.D. 132–135, the Roman Empire recognized Judaism as a legal religion and Christianity as a Jewish sect. As a result of this revolt, the Jews were condemned. To avoid persecution and observe statues that will not identify them with the Jews, some Christians out of fear began to attach some Sabbath sacredness to the first day of the week and observed both days (Saturday and Sunday) for several centuries.
Fourth Century
The Roman emperor Constantine, professed conversion to Christianity to unite the pagans and the Christians. He named himself Bishop of the Catholic Church and enacted the first civil law regarding Sunday observance in A.D. 321. He stated, “On the venerable day of the sun let the magistrate and people residing in cities rest, and let all workshops be closed. In the country however, persons engaged in agricultural work may freely and lawfully continue their pursuits; because it often happens that another day is not so suitable for grain growing or for vine planting; lest by neglecting the proper moment for such operations the bounty of heaven should be lost.” —Schaff’s History of the Christian Church, vol. III, chap. 75.

The first official action of the Catholic Church expressing preference for Sunday was enacted at the Council of Laodicea in 364 A.D. Canon 29 of this council stated that: “Christians shall not Judaize and be idle on Saturday [Sabbath] , but shall work on that day; but the Lord’s day they shall especially honor, and, as being Christians, shall, if possible, do no work on that day. If, however, they are found Judaizing, they shall be shut out from Christ.”
The Change of the Sabbath
The Roman Catholic Church publicly admits it is responsible for changing the Sabbath from Saturday to Sunday. An authoritative catechism for priests states: “But the Church of God [that is, the apostate church] has in her wisdom ordained that the celebration of the Sabbath day should be transferred to ‘the Lord’s day’” (Catechism of the Council of Trent, Donovan translation, 1829 ed., p. 358). This catechism was written by order of this great council, and published under the auspices of Pope Pius V.
Some teach that after the resurrection of Christ, God’s Moral Law (Ten Commandments, (Exodus 20:3-17) was abolished and a new covenant took its place. But Jesus Himself said, “Do not think that I came to destroy the Law or the Prophets. I did not come to destroy but to fulfill. For assuredly, I say to you, till heaven and earth pass away, one jot or one tittle will by no means pass from the law till all is fulfilled” (Matthew 5:17, 18). Therefore, changing the Sabbath from Saturday to Sunday was contrary to God’s will.
It was the Mosaic law, which foreshadowed Christ’s sacrifice (sacrifices, temple ceremonies, and annual Sabbath feasts), that was nailed to the cross (Colossians 2:14-17; Ephesians 2:15) but not God’s moral law, which contains the fourth commandment of the weekly seventh-day Sabbath. Paul affirmed this truth when he wrote: “Do we then make void the law through faith? God forbid; yea, we establish the law” (Romans 3:31).
Christ came to this earth to magnify the law (Isaiah 42:21) and to reveal by His life of perfect obedience that believers can, through the empowering grace of God, give obedience to His law (Philippians 4:13). The plan of justification by faith shows the Lord’s respect for His law in demanding and providing Christ’s sacrifice. If justification by faith abolishes law, then there was no need for the sacrifice of Christ to free the sinner from his guilt, and thus give him peace with God.