And his tabernacle was in Salem Here the reason is assigned why God, putting the Assyrians to flight, vouchsafed to deliver the city of Jerusalem, and to take it under his protection. The reason is, because he had there chosen for himself a dwelling-place, in which his name was to be called upon. The amount, in short, is, first, that men had no ground to arrogate to themselves any share in the deliverance of the city here portrayed, God having strikingly showed that all the glory was his own, by displaying from heaven his power in the sight of all men; and, secondly, that he was induced to oppose his enemies from no other consideration but that of his free choice of the Jewish nation. God having, by this example, testified that his power is invincible for preserving his Church, it is a call and an encouragement to all the faithful to repose with confidence under his shadow. If his name is precious to himself, it is no ordinary pledge and security which he gives to our faith when he assures us that it is his will that the greatness of his power should be known in the preservation of his Church. Moreover, as the Church is a distinguished theater on which the Divine glory is displayed, we must always take the greatest care not to shroud or bury in forgetfulness, by our ingratitude, the benefits which have been bestowed upon it, and especially those which ought to be held in remembrance in all ages. Farther, although God is not now worshipped in the visible tabernacle, yet as by Christ he still dwells in the midst of us, yea even within us, we will doubtless experience, whenever we are exposed to danger, that under his protection we are in perfect safety. If the earthly sanctuary of Jerusalem afforded to God's ancient people succor while it stood, we may rest assured that he will have no less care of us who live in the present day, when we consider that he has vouchsafed to choose us as his temples in which he may dwell by his Holy Spirit. Here the prophet, in speaking of Jerusalem, uses merely the name of Salem, which was the simple and uncompounded name of the city, and had been applied to it very anciently, as appears from Genesis 14:18. Some think that the name in the course of time assumed its compound form, by having Jebus prefixed to Salem; for Jebus was the name by which it was afterwards known in the intervening period, as we learn from the Book of Judges, Judges 19:10, it being so called because it was inhabited by the Jebusites. But we will be more correct as to the etymology of the word, if we derive it from the verb yr'h, yereh, which signifies will see, [1] because Abraham said, "God will look out for himself a lamb for a burnt-offering," (Genesis 22:8.)

Footnotes

1 - From r'h, raäh, he saw, or beheld

In Salem also - This was the ancient name for Jerusalem, and is evidently so used here. It continued to be given to the town until the time of David, when it was called "Jerusalem." See the notes at Isaiah 1:1. The word properly means "peace," and is so rendered here by the Septuagint, ἐν εἰρήνῃ ὁ τόπος αύτοῦ en eirēnē ho topos autou - "his place is in peace." There may have been an allusion here to that ancient signification of the name, as being more poetical, and as suggesting the fact that God had restored peace to the city and nation when invaded.
Is his tabernacle - The tent, or sacred place where he is worshipped. Salem or Jerusalem was made the place of public worship, and the ark removed there by David, 2-Samuel 6:17.
And his dwelling-place in Zion - That is, on Mount Zion - the portion of Jerusalem in which David built his own palace, and which he made the place of public worship. This remained so until the temple was built on Mount Moriah; see the notes at Psalm 2:6; compare Psalm 9:11; Psalm 48:12; Psalm 65:1.

In Salem also is his tabernacle - Salem was the ancient name of Zebus, afterward called Jerusalem. Here was the tabernacle set up; but afterwards, when the temple was built on Mount Zion, there was his habitation. The Psalm was evidently composed after the building of Solomon's temple.

In (b) Salem also is his tabernacle, and his dwelling place in Zion.
(b) Which later was called Jerusalem.

In Salem also is his tabernacle,.... That is, in Jerusalem, as the Targum expresses it, where the tabernacle of Moses and the ark of the covenant were, and afterwards the temple of Solomon, which the Targum here calls the house of the sanctuary; and may be interpreted of the human nature of Christ, the true tabernacle which God pitched, and not man, in which the divine word when he was made flesh dwelt or tabernacled among the Jews at Jerusalem, and in other parts of Judea, Hebrews 8:2. Salem or Jerusalem often signifies the church of God in Gospel times, in the midst of which Christ resides, and where he grants his gracious presence, Hebrews 12:22 and in the New Jerusalem the tabernacle of God will be with men, and he will dwell among them, Revelation 21:2. The Septuagint translate the word, and render it, "in peace", as in Hebrews 7:2, the God of peace dwells among those that live in peace, 2-Corinthians 13:11,
and his dwelling place in Zion; where the ark was brought by David, and the temple was built by Solomon, into which, as rebuilt by Zerubbabel, Christ came, and here he preached; a figure of the church, which is his habitation.

Salem-- (Genesis 14:18) is Jerusalem.

Salem - In Jerusalem, which was anciently called Salem. Zion - Largely so called, as it includes Moriah, an adjoining hill.