John 10:16

16.And I have other sheep. Though some refer this indiscriminately to all, both Jews and Gentiles, who were not yet disciples of Christ, yet I have no doubt that he had in his eye the calling of the Gentiles. For he gives the appellation fold to the assemblage of the ancient people, by which they were separated from the other nations of the world, and united into one body as the heritage of God. The Jews had been adopted by God in such a manner, that he surrounded them with certain enclosures, which consisted of rites and ceremonies, that they might not be confounded with unbelievers, though the door of thefold was the gracious covenant of eternal life confirmed in Christ. For this reason he calls those sheep which had not the same mark, but belonged to a different class, other sheep In short, the meaning is, that the pastoral office of Christ is not confined within the limits of Judea, but is far more extensive.

Augustine’s observation on this passage is undoubtedly true, that, as there are many wolves within the Church, so there are many sheep without But this is not applicable, in every respect, to the present passage, which relates to the outward aspect of the Church, because the Gentiles, who had been strangers for a time, were afterwards invited into the kingdom of God, along with the Jews. Yet I acknowledge that Augustine’s statement applies in this respect, that Christ gives the name of sheep to unbelievers, who in themselves were the farthest possible from being entitled to be called sheep And not only does he point out, by this term, what they will be, but rather refers this to the secret election of God, because we are already God’s sheep, before we are aware that He is our shepherd. In like manner, it is elsewhere said that we were enemies, when he loved us, (Romans 5:10;) and for this reason Paul also says that we were known by God, before we knew him, (Galatians 4:9.)

Them also I must bring. He means that the election of God will be secure, so that nothing of all that he wishes to be saved shall perish. (290) For the secret purpose of God, by which men were ordained to life, is at length manifested in his own time by the calling, — the effectual calling, when he regenerates by his Spirit, to be his sons, those who formerly were begotten of flesh and blood.

But it may be asked, How were the Gentiles brought to be associated with the Jews? For the Jews were not under the necessity of rejecting the covenant which God made with their fathers, in order to become Christ’s disciples; and the Gentiles, on the other hand, were not under the necessity of submitting to the yoke of the Law, that, being ingrafted in Christ, they might be associated with the Jews. Here we must attend to the distinction between the substance of the covenant and the outward appendages. For the Gentiles could not assent to the faith of Christ in any other way than by embracing that everlasting covenant on which the salvation of the world was founded. In this manner were fulfilled the predictions,

Strangers shall speak the language of Canaan,
(Isaiah 19:18.)

Again,

Ten men of the Gentiles shall take hold of the cloak of one Jew, and say,
We will go with you,
(Zechariah 8:23.)

Again,

Many nations shall come, and say,
Come, and let us go up to the mountain of the Lord,
(Isaiah 2:4; Micah 4:2.)

Abraham was also called

a father of many nations, (Genesis 17:5; Romans 4:17,) because they shall come from the East and from the West, who shall sit down with him in the kingdom of God,
(Matthew 8:11.)

As to ceremonies, they are the middle wall of partition, which, Paul informs us, hath been thrown down, (Ephesians 2:14.) Thus, we have been associated with the Jews in the unity of the faith, as to the substance; and the ceremonies were abolished, that there might be nothing to prevent the Jews from stretching out their hand to us.

And there shall be one fold (291) and one shepherd That is, that all the children of God may be gathered and united (292) into one body; as we acknowledge that there is one holy universal Church, (293) and there must be one body with one head.

There is one God, says Paul, one faith, one baptism.
Therefore we ought to be one, as we are called into one hope,
(Ephesians 4:4.)

Now though this flock appears to be divided into different folds, yet they are kept within enclosures which are common to all believers who are scattered throughout the whole world; because the same word is preached to all, they use the same sacraments, they have the same order of prayer, and every thing that belongs to the profession of faith.

And they shall hear my voice. We must observe the way in which the flock of God is gathered. It is, when all have one shepherd, and when his voice alone (294) is heard These words mean that, when the Church submits to Christ alone, and obeys his commands, and hears his voice and his doctrine, (295) then only is it in a state of good order. If Papists can show us that there is any thing of this sort among them, let them enjoy the title of The Church, of which they vaunt so much. But if Christ is silent there, if his majesty is trodden under foot, if his sacred ordinances are held up to scorn, what else is their unity but a diabolical conspiracy, which is worse and far more to be abhorred than any dispersion? Let us therefore remember that we ought always to begin with the Head. Hence also the Prophets, when they describe the restoration of the Church, always join David the king with God; as if they said, that there is no Church where Christ does not reign, and that there is no kingdom of God, but where the honor of shepherd is granted to Christ.