The Sabbath command was never, not once, repeated in the NT. Not even by Jesus when asked, what must I do?
Heb 4:4 For he spake in a certain place of the seventh day on this wise, And God did rest the seventh day from all his works.
Heb 4:8 For if Jesus had given them rest, then would he not afterward have spoken of another day. 9 There remaineth therefore a rest to the people of God.
Paul is using the sabbath rest to illustrate the rest we can have in Jesus.
But nothing is said to say the sabbath rest is replaced or removed.
Jas 2:10-12
10 For whosoever shall keep the whole law, and yet offend in one point, he is guilty of all. 11 For he that said, Do not commit adultery, said also, Do not kill. Now if thou commit no adultery, yet if thou kill, thou art become a transgressor of the law. 12 So speak ye, and so do, as they that shall be judged by the law of liberty.
James is clear, that if you break one law you break all of The LAW.
The sabbath is part of that law mentioned.
Mat 12:12 How much then is a man better than a sheep? Wherefore it is lawful to do well on the sabbath days.
This was written after Jesus died... and Jesus understood what was going to happen. If the sabbath was made void why make the point that it is lawful to do good on the sabbath.
And why would Jesus talk about the Sabbath, in the following verse if it was made void?
Mat 24:20 But pray ye that your flight be not in the winter, neither on the sabbath day: