The Melachos Table was the list of the things that people couldn't do on the Sabbath. These 39 things, however, weren't just things. They were categories of things. That meant that the list of actual things they couldn't do was massive. If someone were to do any of those things, they would be viewed as unholy and a sinner. If people followed these rules to perfection, they were viewed as holy individuals who had a 100% chance of making it to heaven. This is something God really disliked, so he sent Paul to tell them about it.