“The seventh day is the sabbath of the Lord thy God: in it thou shalt not do any work, thou, nor thy son, nor thy daughter, thy manservant, nor thy maidservant, nor thy cattle, nor thy stranger that is within thy gates: For in six days the Lord made heaven and earth, the sea, and all that in them is, and rested the seventh day: wherefore the Lord blessed the sabbath day, and hallowed it.” (Ex.20:10-11)
Nowhere in The Bible has God countermanded that command and man has not got the authority to override a command from God.
Jesus observed it and He is our example.
By all means go to church on the day that was set aside for the Sun God but remember that God set aside another day, The Sabbath. as His day.
Why was Jesus not raised on The Sabbath, the day God had set aside as holy to Himself but was raised on the principle feasr day of the week which was to their main God, and on which everyone in the empire worshipped tis god on?
To show He was greater than this god because this god could not stop Him rising from the dead. By this Jesus showed that Sunday belonged to this god as He had to show He was greater than this god and not that we are to worship on this day.