18The grace of our Lord Jesus Christ be with your spirit, brethren. Amen.
Gal_6:18 This is an example of a brief closing blessing in a cyclical letter (because there are no personal greetings, like Ephesians). Note that the term "be with your spirit" is a good example of the small "s" (spirit) which is used of mankind's spirit, not the Holy Spirit. However, in many instances in the New Testament, it refers to the human spirit, which is energized by the Holy Spirit. This is probably the implication here.