Jamieson, Fausset & Brown

This I say then--Repeating in other words, and explaining the sentiment in Gal 5:13, What I mean is this." Walk in the Spirit--Greek, "By (the rule of) the (Holy) Spirit." Compare Gal 5:16-18, Gal 5:22, Gal 5:25; Gal 6:1-8, with Rom 7:22; Rom 8:11. The best way to keep tares out of a bushel is to fill it with wheat. the flesh--the natural man, out of which flow the evils specified (Gal 5:19-21). The spirit and the flesh mutually exclude one another. It is promised, not that we should have no evil lusts, but that we should "not fulfil" them. If the spirit that is in us can be at ease under sin, it is not a spirit that comes from the Holy Spirit. The gentle dove trembles at the sight even of a hawk's feather.