Lord - Not יהוה Yahweh here, but אדני 'Adonāy. The word is properly rendered “Lord,” but it is a term which is often applied to God. It indicates, however, nothing in regard to his character or attributes except that he is a “Ruler or Governor.”
Thou hast been our dwelling-place - The Septuagint renders this, “refuge” - καταφυγἡ kataphugē. So the Latin Vulgate, “refugium;” and Luther, “Zuflucht.” The Hebrew word - מעון mâ‛ôn - means properly a habitation, a dwelling, as of God in his temple, Psalms 26:8; heaven, Psalms 68:5; Deuteronomy 26:15. It also means a den or lair for wild beasts, Nahum 2:12; Jeremiah 9:11. But here the idea seems to be, as in the Septuagint, Vulgate, and Luther, “a refuge”; a place to which one may come as to his home, as one does from a journey; from wandering; from toil; from danger: a place to which such a one naturally resorts, which he loves, and where he feels that he may rest secure. The idea is, that a friend of God has that feeling in respect to Him, which one has toward his own home - his abode - the place which he loves and calls his own.
In all generations - Margin, “generation and generation.” That is, A succeeding generation has found him to be the same as the previous generation had. He was unchanged, though the successive generations of men passed away.