A student, Sara Whear, noted the inclusio around Galatians 6: Those who are “spiritual” restore one who is caught in a trespass (v. 1) matches the blessing on the “spirit” in v 18. “Bear one another’s burdens” matches Paul’s claim that he “bears the brand-marks of Jesus” (vv. 2, 17). The latter connection suggests that Paul’s brand-marks - the scars of his apostolic suffering - demonstrate that he has fulfilled the law of Christ in bearing the burdens of the church.
In the discussion of Galatians 6, the sowing/reaping imagery of verses 7-8 also came up. Paul is making a general point about actions and consequences, but the terminology he uses is already highly charged by its earlier uses in Galatians. Sowing to the flesh means specifically promoting circumcision and other “fleshly” rites and practices; those who sow to the flesh are Judaizers, and they will harvest corruption. Those who sow to the Spirit are those who have both received the Spirit by hearing in faith and seek to be perfected in the Spirit (3:1-5); sowing in the Spirit involves fulfilling the law of Christ by bearing one another’s burdens.