" This is another way of stating the principle that `the labourer deserves his wages' (Lk. 10:7; 1 Tim. 5:18; cf. Mt. 10:10) or, as Paul elsewhere paraphrases those words of Jesus, `those who proclaim the gospel should get their living by the gospel' (1 Cor. 9:14). "

― F.F. Bruce , Epistle to the Galatians (New International Greek Testament Commentary)