What we find in the Bible are the practices and commands given to the churches by the apostles whom Jesus chose and equipped to teach on His behalf. One of these practices was assembling on the first day of the week to partake in the memorial feast, etc.
Now we can call it “Firstday” if the more common “Sunday” offends us. But whatever we call it, it’s the day after the Sabbath. The Sabbath is the seventh day, and there are seven days in the week. So the early disciples, under the direction of Jesus’ own apostles, assembled on the first day of the week, just as we read about in Acts 20.
Roamer_1 explained Acts 20 in his previous post.
But what I want to point out is this. IF the dissolution of the 4th commandment was taught by Christ and understood as such by his followers then it begs a couple of questions:
1. Why no controversy? The sabbaths are in the bible. They had been observed by Israelites for thousands of years. Surely there would have been an uproar and discussion among early Christians and persecution by Jews. By contrast look at the issue of circumcision...huge controversy that reverberates throughout scripture and it wasn't even one the ten big ones! Nah, it's clear that very early Christians kept the sabbath.
2. Look at traditional church history. The issue of whether to keep the biblical sabbaths wasn't officially decided until 360 AD (or thereabouts). It's exactly because there was no biblical precedent for it. Those verses you're going to point to are all latter day justification for abandoning it. There are just as many, if not more, new testament references to sabbath worship and observance.
How does that remove the command to keep the Sabbath Day?