Jesus observed the Sabbath (Luke 4:16) and never suggested a change to Sunday.
He did, However reject a strict legalistic interpretation of the Old Testament commandment. He said Sabbath observance was not a duty that mankind owed to God.Rather, God made the Sabbath as a day of rest for mankind’s benefit (Mark 2:27). Jesus and His disciples did not observe the strict Jewish rules against doing any work on the Sabbath (Matthew 12:1-14, Mark 2:23-28, 3:1-6, Luke 6:1-11, 13:10-17, 14:1-6, John 5:1-18).
In the early centuries of Christianity, all the Christian communities of the world were under control of the Roman Empire.Constantine was the first Roman emperor to convert to Christianity. In 321 A.D. he proclaimed Sunday a legal day of rest and ordered all judges, city-people and craftsmen to rest.By this time, the Christian Church had lost contact with its Jewish roots, and there was much hostility between Christians and Jews. Jewish Christians had been expelled from the synagogues as heretics (John 9:22, 16:2, 1)
Thessalonians 2:14-16). This hostility may have influenced Christians to abandon Sabbath observances. In about 363 A.D., declared that Christians must not rest on the Sabbath (Saturday), but must work on that day, rather honoring the Lord’s Day (Sunday).
Today, most Christians follow the tradition of holding worship services on Sunday. But some believe that Saturday, the original Sabbath day, is the proper day for rest and worship. Many Christians consider Sunday to be the new Sabbath day, and they believe the Old Testament rules against working on the Sabbath apply to Sunday. However, there is nothing in the Bible which prohibits doing work on Sunday.