In 325 A.D., Sabbath (seventh day) keeping became Sunday (first day) keeping, according to the decision of the Council of Nicea, whose members were the Roman emperor Constantine, Pope Silvester I, and over 300 Catholic bishops. This decision was endorsed by civil law and backed by military force.
God never changed Sabbath keeping to Sunday keeping. Sunday keeping is a tradition started by man nearly 1700 years ago.
Elohim (God, the Creator) put the seventh day above all other days when He blessed and sanctified it. He blessed and sanctified it for rest, fellowship and worshipping Him, then commanded us to keep it holy.
Genesis 2:2-3; Exodus 20:8
Jesus, who is our example, kept the Sabbath. He kept the Sabbath even in the grave and did not rise until early Sunday morning.
Mark 6:2, Luke 4:16, Mark 16:1-2, 9
From the beginning and during the time of Jesus, the majority of the world kept the Sabbath. Acts 13:14-15, 44; 16:13
Jesus did not take Sabbath keeping out of the way; neither did He take the Sabbath day out of the way. He only took the seven ceremonial Sabbaths out of the way. Colossians 2:14-16
God has promised special blessings to those that keep the Sabbath.
Isaiah 56:2, 58:13-14
In Isaiah 66:23,God says,“And it shall come to pass, that from one new moon to another, and from one sabbath to another, shall all flesh come to worship before me…”
You can go to heaven worshipping God on Sunday, or any other day that
you choose to be your high day. We have chosen the Sabbath (seventh day) for our high day to worship God, because it is His command.
Genesis 2:3, Exodus 20:8