Imagine someone thinking that they could take one of the great masterpieces of art and you know ... make it a little better with a few additions. Doing so would render the Chagall, the Rembrandt, or the Degas worthless.
The churches in ancient Turkey were being encouraged to make some additions like that to the masterpiece of grace known as the Gospel of Jesus. And in doing so, making the good news not good at all.
Paul, the apostle of Jesus, makes one final appeal not to add religious rules to the masterpiece in his letter to the Galatians (ancient Turkey) in chapter 5 and verses 1-12. Appealing to the 21st century to see again that God's love cannot be bought with our rule keeping