[Isaiah] announces the wonderful and widespread demonstration of piety everywhere: idolatry will be destroyed, while the house of God will receive its due sign of universal respect. . . . After our Savior’s appearing, idolatry will be shown and the beauty of truth will be unveiled. In this we will see the fulfillment of this announcement. Furthermore, by last days he means that time following incarnation.

He calls the church a mountain when he says, In the last days the mountain of the Lord’s house shall be established.

The central place they are all coming to is Christ; he is at the center, because he is equally related to all; anything placed in the center is common to all. . . .

Approach the mountain, climb up the mountain, and you that climb it, do not go down it. There you will be safe, there you will be protected; Christ is your mountain of refuge. And where is Christ? At the right hand of the Father, since he has ascended into heaven.

It talks of a mountain, and the mountain is veiled to the party of Donatus.^[1] . . .

The holy Daniel saw a vision and wrote down what he saw, and he said that he had seen a stone hewn out of a mountain without hands. It is Christ, coming from the nation of the Jews, which was also a mountain, you see, because it has the kingdom. . . .

What is the mountain over which the heretics stumbled? Listen to Daniel again: And that stone grew and became a great mountain, such that it filled all the face of the earth.^[2] How right the psalm is to say to Christ the Lord as he rises again, Be exalted over the heavens, O God, and let your glory be over the whole earth.^[3] What is your glory over the whole earth? Over the whole earth your church, over the whole earth your bride.

Who is meant by mountain of strength but our Redeemer?

One can take the time to learn in what manner the prophecies of the call of the Gentiles should be understood and that they were fulfilled only after the coming of our Savior. The beginning of the prophecy is consistent with the reality that the Lord descended not only for the salvation of the Jewish race but also for that of all people, in announcing to all peoples and all the inhabitants of the earth, Hear, all peoples, and let the earth and all in it listen.

The mountain is Christ, and the house of the God of Jacob is his one church, toward which the concourse of nations and assembly of peoples is moving by this pronouncement.

This mountain is in the house of the Lord, for which the prophet sighed when he said, One thing I asked from the Lord, this I seek, that I might dwell in the house of the Lord all the days of my life,^[1] and about which Paul wrote to Timothy, If I am late, you should know how to behave in the house of God, which is the church of the living God, the pillar and foundation of the truth.^[2] This house was built on the foundation of the apostles and the prophets,^[3] who are mountains themselves as imitators of Christ. About this house of Jerusalem the psalmist cried out: Those who trust in the Lord are like Mount Zion, which dwells in Jerusalem; it will not be moved forever. The mountains surround her and the Lord surrounds his people.^[4] Hence Christ also founds his church on one of the mountains and says to him, You are Peter, and on this rock I will build my church, and the gates of the netherworld will not prevail against her.^[5]

Let us sing a victorious song of praise to the Lord!

Who will lead us to such a company of angels? Who, longing for the heavenly feast and the angels’ holiday, will say like the prophet, I will lead them to the house of God: a multitude joyfully praising God and keeping festival?^[1] The saints of old encourage us to be like that, saying, Come, let us go up to the mountain of the Lord, and to the house of the God of Jacob.

I am amazed at the persistence of some to interpret this passage in such a way as to conclude that this is a prediction of the return from Babylonian captivity. Which nations rushed to the temple after its rebuilding? What law was given from there? God gave the ancient law on Sinai, not Zion. Clearly Isaiah is referring to the New Testament, where the law was first given to the apostles and then delivered to all peoples by them. He announces that in addition to the law, the word would come from Zion. The term word is a title given to the message of the gospel. The blessed Luke says, Those who were from the beginning eyewitnesses and ministers of the word delivered them to us.^[1] He is not talking about God the Word but the message of the divine word. Zion is not where God the Word was from but where he taught the truth.

Ask a man of circumcision, a Jew after the flesh, which law and which word the prophet is talking about. About the law given through Moses? Let them show how this law comes out of Zion. For Moses did not enter the land of possession, whereas Zion is in Judea.^[1] The Scripture was mistaken then, according to them, using one name instead of another, for it said Zion instead of Sinai or Horeb. But it refers to the holy law. Which one? When was it given? Where was it written? And the word out of Jerusalem as well? The Jew after the flesh says that Isaiah means preaching of the prophets. Yet the preaching of the prophets took place everywhere across Judea, not only in Jerusalem and throughout Israel but also in captivity, in Nineveh and throughout the earth. Let them restrain themselves then before the truth and receive the law giving of the Lord that comes from the watchtower, the God-bearing flesh from which he watched over human actions. And the word of the Lord out of Jerusalem. Having started from there, the preaching of the gospel has been sown around the whole world.

We can show you that this actually happened. For a group of twelve men went out from Jerusalem, and they were ignorant men, not trained in oratory. But through the power of God they witnessed to every race of humanity that they were sent out by Christ to teach the Word of God to all people. Now we who once killed one another no longer war against each other, but moreso we gladly die for the confession of Christ in order not to lie to or deceive our interrogators.^[1]

What can this law proceeding from Zion, which is different from what was made law by Moses in the desert at Mount Sinai, be but the word of the gospel through our Savior Jesus Christ which proceeds from Zion through all the nations? For clearly it was in Jerusalem and Mount Zion, where our Savior and Lord lived and taught, that the law of the new covenant originated and from which it proceeded to all people.

The first law, the Old Testament, had come out of Mount Sinai by the lips of Moses; but it was foretold of the law Christ came to give: The law shall come forth from Zion, and the word of the Lord from Jerusalem. This explains why Christ ordered repentance to be preached in his name among all peoples but beginning in Jerusalem.

It was opportune that the preaching of repentance and the forgiveness of sins through confession of Christ’s name should have started from Jerusalem. Where the splendor of his teaching and virtues, where the triumph of his passion, where the joy of his resurrection and ascension were accomplished, there the first root of faith in him would be brought forth; [there] the first shoot of the burgeoning church, like that of some kind of great vine, would be planted. Just so, by an increase in the spreading of the word, [the church] would extend the branches of her teaching into the whole wide world. . . . It was opportune that the preaching of repentance and the forgiveness of sins, good news to be proclaimed to idolatrous nations and those defiled by various evil deeds, should take its start from Jerusalem, lest any of those defiled, thoroughly terrified by the magnitude of their offenses, should doubt the possibility of obtaining pardon if they performed fruits worthy of repentance, when it was a fact that pardon had been granted to those at Jerusalem who had blasphemed and crucified the Son of God.

Long ago did Isaiah declare that out of Zion should go forth the law, and the word of the Lord from Jerusalem, some other law, that is, and another word. In short, he says, He shall judge among the nations and shall rebuke many people, meaning not those of the Jewish people only, but also of the nations which are judged by the new law of the gospel and the new word of the apostles, and are among themselves rebuked of their old error as soon as they have believed. And as the result of this, They beat their swords into plowshares, and their spears (which are a kind of hunting instrument) into pruning hooks. That is to say, minds that once were fierce and cruel are changed by the gospel and the word of the apostles into good dispositions productive of good fruit.

The gospel will be this way of the new law and the new word in Christ, no longer in Moses. And he shall judge among the nations, even concerning their error. And these shall rebuke a large nation, that of the Jews themselves and their proselytes. And they shall beat their swords into plowshares; in other words, they shall change into pursuits of moderation and peace the dispositions of injurious minds, hostile tongues and all kinds of evil and blasphemy. . . . You learn here that Christ is promised not as powerful in war but pursuing peace.

Who is the one who has done this, or who is the one who has joined together in peace people who once hated one another, except for the beloved Son of the Father, the Savior of all, even Jesus Christ, who because of his own love suffered all things for our salvation? For from ages past the peace he would initiate was promised.

Not only would the church be firm, steadfast and indestructible, but it would also gain great peace for the world. Governments and monarchies will be destroyed; there will be but one kingdom put together for all people, and, unlike in times past, its greater part will be at peace. For, in the past, all craftsmen and men in public life were trained in warfare and took their place among the ranks. After the coming of Christ, all that was done away with, and wars were confined to widely separated areas.

Our conclusion is that there were two seeds of Judah and two races, just as there are two houses of Jacob, one born of flesh and blood and the other born of faith and the Spirit.

What did the prophet Isaiah mean when he announced that a mountain would be prepared on the summits of the mountains, to which all peoples were going to come? The law and the Word of God was going to proceed from Zion and Jerusalem to all nations, not from Mount Sinai to one nation. This we see most evidently fulfilled in Christ and the Christians. A little later the prophet says, O house of Jacob, come and let us walk in the light of the Lord. Here, you [the Jews] will surely say your usual piece: We are the house of Jacob, but listen a moment to what follows, and when you have said what you want to say, hear what you do not want to hear. The prophet continues, For he has cast off his people, the house of Israel. Here say, We are the house of Israel; here acknowledge yourselves and forgive us for reminding you of these facts.

Dearly beloved, whether the Jews receive these divine testimonies with joy or with indignation, nevertheless, when we can, let us proclaim them with great love for the Jews. Let us not proudly glory against the broken branches; let us rather reflect by whose grace it is, and by much mercy, and on what root, we have been grafted into.

For all who do evil hate the light and fail to come to the light lest their works be proven.^[1] But you, the house of Jacob, the house of my people, come with me and let us walk together in the light of the Lord. Let us accept the gospel of Christ and be illuminated by him who said, I am the light of the world.^[2] And when this had been spoken to the people of the Jews, discerning that their hearts were impenitent and their hardened souls unbelieving, Isaiah made a note to the Lord, saying, I exhort them, therefore, to come to you today and to be filled with me by your light, for you have abandoned your people, formerly the house of Jacob, on account of their sins.

Someone might ask, what is wrong with having silver or horses, particularly when what the people believed was not rigorous? How should we respond? The prophet was not criticizing the use of these possessions but the misuse of them. When he said, Woe to the mighty,^[1] he was not condemning them for having possessions but for hoarding so much more than they needed.

Not only do human beings make gods for themselves^[1] from statues, but you will also find them making gods for themselves from their imaginations. For such people can imagine another god and creator of the world in a system different from the divine plan of the world recorded by the Spirit, other than the true world. These all have made gods for themselves, and they have worshiped the works of their hands. So, too, I believe is the case either among the Greeks who generate opinions, so to speak, of this philosophy or that, or among the heretics, the first who generate opinions. These have made idols for themselves and figments of the soul, and by turning to them they worship the works of their hands, since they accept as truth their own fabrications.

Vanity is the general term for vices, but vain in the particular sense means that which is found alien to God. Just as trusting in the Godhead is fruitful constancy, so deviating from him is the vanity that perishes. . . . So those who burned with the most base love of idols are convicted, and the phrase is to be pronounced as a rebuke, as if the words were, Why do you love the vanity by which you perish? We ought to love things that are beneficial, not harmful, for it is better to curse the things that cause the punishment of lasting damnation to afflict us.

The Creator ought to be known even by the light of nature, for he may be understood from his works and may thereby become the object of a more widely spread knowledge. To him, therefore, does it appertain to punish such as do not know God, for none ought to be ignorant of him. In the apostle’s phrase, From the presence of the Lord, and from the glory of his power,^[1] he uses the words of Isaiah, who for that same reason attests the very same Lord as arising to shake terribly the earth.^[2]