From the time of ancient Egypt and even ancient Babylon, the sun was the main false god (Ra the sun god). Idol worshippers chose a day to honor their false god and called it “Sunday”.
After the death and resurrection of Christ the enemies of our Lord were successful in infiltrating the true Church as the scriptures warned.
Matthew 24:11: “And many false prophets shall arise, and shall deceive many.”
Acts 20:29: “For I know this, that after my departing shall grievious wolves enter in among you, not sparing the flock.” Verse 30 “Also of your own selves shall men arise, speaking perverse things, to draw away disciples after them.”
After Paul and the other disciples died many false teachers entered into the church bringing lies/heresies. In time, these heretics taught that the Sabbath which God had given as a memorial of His creation was done away by Christ and Sunday was exalted as the Lord‘s day. This made it much easier for idol worshippers to come into the church and increase the financial income of the church; if the Christians met on the same day that the pagan world did.
There are only eight scriptures in the New Testament that mention the first day of the week.
Matthew 28:1: “In the end of the sabbath, as it began to dawn toward the first day of the week, came Mary Magdalene and the other Mary to see the sepulchre.”
Mark 16:1: “And when the sabbath was past, Mary Magdalene, and Mary the mother of James, and Salome, had bought sweet spices, that they might come and anoint him.”
2: “And very early in the morning the first day of the week, they came unto the sepulchre at the rising of the sun.”
Mark 16:9: “Now when Jesus was risen early the first day of the week, he appeared first to Mary Magdalene, out of whom he had cast seven devils.”
Luke 24:1: “Now upon the first day of the week, very early in the morning, they came unto the sepulchre, bringing the spices which they had prepared, and certain others with them.”
John 20:1: “The first day of the week cometh Mary Magdalene early, when it was yet dark, unto the sepulchre, and seeth the stone taken away from the sepulchre.”
John 20:19: “Then the same day at evening, being the first day of the week, when the doors were shut where the disciples were assembled for fear of the Jews, came Jesus and stood in the midst, and saith unto them, Peace be unto you.”
Acts 20:7: “And upon the first day of the week, when the disciples came together to break bread, Paul preached unto them, ready to depart on the morrow; and continued his speech until midnight.”
8: “And there were many lights in the upper chamber, where they were gathered together.”
1 Corinthians 16:1: “Now concerning the collection for the saints, as I have given order to the churches of Galatia, even so do ye.”
2: “Upon the first day of the week let every one of you lay by him in store, as God hath prospered him, that there be no gatherings when I come.”
Notice the first five scriptures simply state that the Israelite women came to the sepulcher early in the morning and that Christ had already risen from the dead. Pagan church leaders teach that the followers of Christ gathered on the first day of the week because of some new law but John 20:19 says that the Lord appeared to the disciples later in the day and that the reason they assembled on the first day of that week was “for FEAR of the Jews”.
The seventh verse was Acts 20:7,8. It shows us that the disciples gathered to hear Paul preach because he was going to depart on the morrow (so called Monday) this is a farewell get together.
The eighth and last verse was 1 Corinthians 16:1,2; which was about the believers coming together for the purpose of gathering money. Paul wanted this money already prepared when he got there to take it to the poor Israelites in Jerusalem.
There is NO mention in either of those verses that teach us about a change of the Lord’s Sabbath to Sunday.
This is what Christ taught concerning this matter:
Matthew 5:17: “Think not that I am come to destroy the law, or the prophets: I am not come to destroy, but to fulfill.”
Matthew 12: 8: “For the Son of man is Lord even of the sabbath day.”
SHALOM.