1.
And the congregation of the peoples let it compass You about: And over it return You on high.
He speaks of congregation (עדת) in a general, and of peoples (לאמים) in a specific, sense. The congregation is the congregation of Israel, which includes them all; the peoples (לאמים) are the twelve tribes of Israel. And they are called לאמים, i.e. peoples (עמים) and nations (גוים), as Isaac said to Jacob: "that thou mayest be a company of peoples (עֹמים קהל)" (Gen. 28:3). And so God says to Jacob (ibid. 35:11): "A nation and a company of nations (גוים קהל) shall be of thee." So you see he calls them "peoples" (עמים) and "nations" (גוים) relative to the tribes; and he calls them a " company " (קהל) and a "congregation" (עדה), for the twelve tribes formed one company and one congregation. If he were using the word לאמים ("peoples") of the nations of the world, he would not have made use of the expression congregation (ועדת), for a single congregation could not comprise them (all), because every single people (לאום) forms a congregation by itself in its own sight.
...the interpretation of this verse will be as follows:
It was known in Israel that David had been anointed to be king, and it was known likewise also that Samuel had anointed him at God's direction. And in the place where he had been anointed all recognised that Samuel had not done this of his own mind, for when Eliab, (David's) eldest brother, came he said, "Surely the Lord's anointed is before Him" (i Sam. 16:6), for he thought that he was to be the king until the Lord said to him: "Look not on his countenance nor on the height of his stature" (ibid. 5:7). And when the youngest came God said to him, "Arise, anoint him, for this is he" (ibid. 5:12). If so, he who pursued after David was as though he pursued after God, and he who surrounded him to capture him as one who surrounded God, who is blessed. And because of this he says, Let it compass thee about, after the manner of the prophet (Zech. 2:12), who says: "for he that toucheth you is as one who toucheth the apple of his eye." And when he says, And over it return Thou on high, it is as he has (just before) said, Arise and lift up Thyself. And it is all figurative, for when God forgives man's transgression, it is as though He should descend from His place of power and His habitation of judgment. And when He visits man's iniquity and judges him, then it is as though He should rise and lift Himself up and return on high to the place of judgment. And so it is said of the vengeance on Pharaoh (Exod. 15:1), "for He is highly exalted."