Walk in the Spirit; the apostle having, Gal_5:13, cautioned them against turning the grace of God into wantonness, by using their liberty as an occasion to the flesh; here he directeth them to the best means for the avoiding thereof, viz.
walking in the Spirit. Where by Spirit he doth not mean our own spirits, or the guide and conduct of our own reason; for the term Spirit, set (as here) in opposition to the flesh, is in no place of Scripture understood of any other than the Holy Spirit of God, which dwelleth in and influenceth believers, guiding them both by a rule from without, (which is the word of God, given by its inspiration), and by its inward motions and operations. Walking, signifieth the directing of their whole conversations. The phrases
in the Spirit, and after the Spirit, Rom_8:1, seem to be of the same import, uuless the alteration of the preposition signifieth, that Christians are not only to look to the word of God dictated by the Holy Spirit as their rule, and to listen to its dictates, but also to look up to the Holy Spirit for its strength and assistance; and implieth a promise of such assistance. The sense is: Let your whole conversation be according to the external rule of the gospel, and the more inward motions, directions, and inclinations of the Spirit of Christ, dwelling and working in you, and moving you to the obedience of that word.
And ye shall not fulfil the lust of the flesh; this doing, though the flesh be yet in you, and you will find the lustings and warrings of it, yet you shall not fulfil the sinful desires and lustings of it; that is, sin, though it be in you, shall not be in dominion in you; it shall not reign in your mortal bodies: Rom_6:12: Let not sin reign in your mortal body, that ye should obey it in the lusts thereof.