By That was in essence the local newspaper headline in every city where the apostles of Jesus preached during the first few decades after Jesus had ascended into Heaven. In Acts 17:6 the people of the city of Thessalonica (modern day Thessaloniki) described the Apostles to the city officials as “men who have turned the world upside down” by preaching about Jesus.
In reality the world is upside down as far as morality, worship, and truth is concerned. As Christians we know what is right and wrong, who the true God is, and where to find truth. We are therefore those who are right-side-up in an upside-down world. The world, thinking it is right-side-up should indeed say about us “these people turn everything upside down.”
Do not conform to the world, but be transformed (Romans 12:2) so you can prove to all what God’s will for us is.