What do you do with the several times in Scripture where it says the Christians met in fellowship on the “first day of the week”? Paul spoke of it several times, in fact. Though the early Christians continued to observe Sabbath and go to the temple (those who were Jewish), they also started meeting on Sunday (which was the first day of the week) in remembrance of the day the Lord was resurrected. This eventually became the custom as more and more Gentiles came to faith in Christ. I do not think they did this to covertly honor the pagan sun god. What are your thoughts? Should Christians NOT worship and meet together on Sunday as was the custom of the Apostles and the early Christians?
You then need to also deal with the Scripture that talks about not judging another on the feast days or sabbaths that they observe. One man esteemeth one day above another: another esteemeth every day alike. Let every man be fully persuaded in his own mind. (Romans 1:5) Thank you.