3:21 Who shall change our vile body. Who shall fashion anew the body of our humiliation (Revised Version). Our lowly body shall undergo a change to fit it for heaven.
That it may be fashioned like unto his glorious body. It will take the form of his glorified body, such as was seen at the Transfiguration. Compare 1Co 15:43-52; 2Co 5:1-4 1Jo 3:2.
According to the working whereby he is able even to subdue all things unto himself. This change shall be effected in harmony with that mighty power which shall subdue all things to his sway.
3:21 Who will transform our vile body - Into the most perfect state, and the most beauteous form. It will then be purer than the unspotted firmament, brighter than the lustre of the stars and, which exceeds all parallel, which comprehends all perfection, like unto his glorious body - Like that wonderfully glorious body which he wears in his heavenly kingdom, and on his triumphant throne.
3:12-21 This simple dependence and earnestness of soul, were not mentioned as if the apostle had gained the prize, or were already made perfect in the Saviour's likeness. He forgot the things which were behind, so as not to be content with past labours or present measures of grace. He reached forth, stretched himself forward towards his point; expressions showing great concern to become more and more like unto Christ. He who runs a race, must never stop short of the end, but press forward as fast as he can; so those who have heaven in their view, must still press forward to it, in holy desires and hopes, and constant endeavours. Eternal life is the gift of God, but it is in Christ Jesus; through his hand it must come to us, as it is procured for us by him. There is no getting to heaven as our home, but by Christ as our Way. True believers, in seeking this assurance, as well as to glorify him, will seek more nearly to resemble his sufferings and death, by dying to sin, and by crucifying the flesh with its affections and lusts. In these things there is a great difference among real Christians, but all know something of them. Believers make Christ all in all, and set their hearts upon another world. If they differ from one another, and are not of the same judgment in lesser matters, yet they must not judge one another; while they all meet now in Christ, and hope to meet shortly in heaven. Let them join in all the great things in which they are agreed, and wait for further light as to lesser things wherein they differ. The enemies of the cross of Christ mind nothing but their sensual appetites. Sin is the sinner's shame, especially when gloried in. The way of those who mind earthly things, may seem pleasant, but death and hell are at the end of it. If we choose their way, we shall share their end. The life of a Christian is in heaven, where his Head and his home are, and where he hopes to be shortly; he sets his affections upon things above; and where his heart is, there will his conversation be. There is glory kept for the bodies of the saints, in which they will appear at the resurrection. Then the body will be made glorious; not only raised again to life, but raised to great advantage. Observe the power by which this change will be wrought. May we be always prepared for the coming of our Judge; looking to have our vile bodies changed by his Almighty power, and applying to him daily to new-create our souls unto holiness; to deliver us from our enemies, and to employ our bodies and souls as instruments of righteousness in his service.