In the dramatic concluding section, Galatians 6:11-18, Paul brought the whole message of the letter together by writing about boasting. He contrasted worldly religious boasting with Christian boasting. Christians are to boast only in something that was and is despised by most people: the instrument of execution known as a cross.
In order to be strong in the Lord’s strength, Christians need to put on the whole armor of God.
Paul's ministry took some unexpected turns, but through it all the Lord showed He was in control.
While the Old Testament is still valid, we also have the message of the one who was raised from the dead.