Isaiah 55:10

This is set forth under a figure drawn from the rain and the snow. "For as the rain cometh down, and the snow from heaven, and returneth not thither, till it has moistened the earth, and fertilized it, and made it green, and offered seed to the sower and bread to the eater; so will my word be which goeth forth out of my mouth: it will not return to me fruitless, till it has accomplished that which I willed, and prosperously carried out that for which I sent it." The rain and snow come down from the sky, and return not thither till they have .... The perfects after אם כּי are all to be understood as such (Ewald, 356, a). Rain and snow return as vapour to the sky, but not without having first of all accomplished the purpose of their descent. And so with the word of Jehovah, which goeth forth out of His mouth (יצא, not יצא, Isa 45:23, because it is thought of as still going on in the preaching of the prophet): it will not return without having effected its object, i.e., without having accomplished what was Jehovah's counsel, or "good pleasure" - without having attained the end for which it was sent by Jehovah (constr. as in Sa2 11:22; Kg1 14:6). The word is represented in other places as the messenger of God (Isa 9:8; Psa 107:20; Psa 147:15.). The personification presupposes that it is not a mere sound or letter. As it goeth forth out of the mouth of God it acquires shape, and in this shape is hidden a divine life, because of its divine origin; and so it runs, with life from God, endowed with divine power, supplied with divine commissions, like a swift messenger through nature and the world of man, there to melt the ice, as it were, and here to heal and to save; and does not return from its course till it has given effect to the will of the sender. This return of the word…

As we had much of Christ in the 53rd chapter, and much of the church of Christ in the 54th chapter, so in this chapter we have much of the covenant of grace made with us in Christ. The "sure mercies of David," which are promised here (Isa 55:3), are applied by the apostle to the benefits which flow to us from the resurrection of Christ (Act 13:34), which may serve as a key to this chapter; not but that it was intended for the comfort of the people of God that lived then, especially of the captives in Babylon, and others of the dispersed of Israel; but unto us was this gospel preached as well as unto them, and much more clearly and fully in the New Testament. Here is, I. A free and gracious invitation to all to come and take the benefit of gospel grace (Isa 55:1). II. Pressing arguments to enforce this invitation (Isa 55:2-4). III. A promise of the success of this invitation among the Gentiles (Isa 55:5). IV. An exhortation to repentance and reformation, with great encouragement given to hope for pardon thereupon (Isa 55:6-9). V. The ratification of all this, with the certain efficacy of the word of God (Isa 55:10, Isa 55:11). And a particular instance of the accomplishment of it in the return of the Jews out of their captivity, which was intended for a sign of the accomplishment of all these other promises.

55:10-11 The Creator not only sends rain and snow but also his word (Hebrew dabar). In this context, dabar means his will or plan (see 14:24; 40:8). God’s written word, as an expression of God’s plan, accomplishes his purposes. God is effective in whatever he does (see 14:26-27; 46:10).