To confirm the certainty of this most joyful turn of events, the promise closes with the summons in Hosea 2;Hos 1:1-11 : “Say ye to your brethren: My people; and to your sisters, Favoured.” The prophet “sees the favoured nation of the Lord (in spirit) before him, and calls upon its members to accost one another joyfully with the new name which had been given to them by God” (Hengstenberg). The promise attaches itself in form to the names of the children of the prophet. As their names of ill omen proclaimed the judgment of rejection, so is the salvation which awaits the nation in the future announced to it here by a simple alteration of the names into their opposite through the omission of the לֹא.
So far as the fulfilment of this prophecy is concerned, the fact that the patriarchal promise of the innumerable multiplication of Israel is to be realized through the pardon and restoration of Israel, as the nation of the living God, shows clearly enough that we are not to look for this in the return of the ten tribes from captivity to Palestine, their native land. Even apart from the fact, that the historical books of the Bible (Ezra, Nehemiah, and Esther) simply mention the return of a portion of the tribes of Judah and Benjamin, along with the priests and Levites, under Zerubbabel and Ezra, and that the numbers of the ten tribes, who may have attached themselves to the Judaeans on their return, or who returned to Galilee afterwards as years rolled by, formed but a very small fraction of the number that had been carried away (compare the remarks on 2Ki 17:24); the attachment of these few to Judah could not properly be called a union of the sons of Israel and of the sons of Judah, and still less was it a fulfilment of the word, “They appoint themselves one head.” As the union of Israel with Judah is to be effected through their gathering together under one head, under Jehovah their God and under David their king, this fulfilment falls within the Messianic times, and hitherto has only been realized in very small beginnings, which furnish a pledge of their complete fulfilment in the last times, when the hardening of Israel will cease, and all Israel be converted to Christ (Rom 11:25-26). It is by no means difficult to bring the application, which is made of our prophecy in 1Pe 2:10 and Rom 9:25-26, into harmony with this. When Peter quotes the words of this prophecy in his first epistle, which nearly all modern commentators justly suppose to have been written to Gentile Christians, and when Paul quotes the very same words (Hos 2:1, with Hos 1:10) as proofs of the calling of the Gentiles to be the children of God in Christ; this is not merely an application to the Gentiles of what is affirmed of Israel, or simply the clothing of their thoughts in Old Testament words, as Huther and Wiesinger suppose, but an argument based upon the fundamental thought of this prophecy. Through its apostasy from God, Israel had become like the Gentiles, and had fallen from the covenant of grace with the Lord. Consequently, the re-adoption of the Israelites as children of God was a practical proof that God had also adopted the Gentile world as His children. “Because God had promised to adopt the children of Israel again, He must adopt the Gentiles also. Otherwise this resolution would rest upon mere caprice, which cannot be thought of in God” (Hengstenberg). Moreover, although membership in the nation of the Old Testament covenant rested primarily upon lineal descent, it was by no means exclusively confined to this; but, from the very first, Gentiles also were received into the citizenship of Israel and the congregation of Jehovah through the rite of circumcision, and could even participate in the covenant mercies, namely, in the passover as a covenant meal (Exo 12:14). There was in this an indirect practical prophecy of the eventual reception of the whole of the Gentile world into the kingdom of God, when it should attain through Christ to faith in the living God. Even through their adoption into the congregation of Jehovah by means of circumcision, believing Gentiles were exalted into children of Abraham, and received a share in the promises made to the fathers. And accordingly the innumerable multiplication of the children of Israel, predicted in Rom 9:10, is not to be restricted to the actual multiplication of the descendants of the Israelites now banished into exile; but the fulfilment of the promise must also include the incorporation of believing Gentiles into the congregation of the Lord (Isa 44:5). This incorporation commenced with the preaching of the gospel among the Gentiles by the apostles; it has continued through all the centuries in which the church has been spreading in the world; and it will receive its final accomplishment when the fulness of the Gentiles shall enter into the kingdom of God. And as the number of the children of Israel is thus continually increased, this multiplication will be complete when the descendants of the children of Israel, who are still hardened in their hearts, shall turn to Jesus Christ as their Messiah and Redeemer (Rom 11:25-26).