v5, v13: Notice how it was always the Jews that made trouble for the apostles?
Acts 17 6 and 7: "and when they found them not they drew Jason and certain brethren unto the rulers of the city crying these that have turned the world upside down are come hither also whom Jason hath received and these all do contrary to the decrees of Caesar saying that there is another king Jesus"
Christianity turned the world upside down. Now the thing most Christians want to do is conform to the world.
The thing about real Christianity that has always angered rulers and powerful people throughout the centuries is that true Christianity teaches that people should follow God's law rather than man's.
Acts 17 26: "and hath made of one blood all nations of men for to dwell on the face of the earth and hath determined the times before appointed and the bounds of their habitation"
God is a god of borders. He likes people's to be in their own separate territories.
Acts 19 27: "so that not only this our craft is in danger to be set at nought but also that the temple of the great goddess Diana should be despised and her magnificence should be destroyed whom all Asia and the whole world worshippeth"
The same thing could be said about Princess Diana: the whole world worshipped her.
Acts 20 7: "and upon the first of the week when the disciples came together to break bread Paul preached unto them ready to depart on the morrow and continued his speech until midnight"
This verse in no way indicates that the day of worship was changed from Saturday to Sunday. Just because they had gathered together on Sunday doesn't mean they didn't also gather to worship on the sabbath.