Thy throne is stable Some read, is prepared, and this agrees well with the context. provided we take the two clauses as one sentence, meaning -- O Lord, as thou art from eternity, even so thy throne is erected or prepared from that time For the sense which some have attached to the words, as if they contained a simple assertion of God's eternity, is poor; and the Psalmist evidently intends to say that as God is eternal in essence, so he has always been invested with power and majesty. The term throne signifies, by the figure synecdoche, righteousness, and office or power of government; it being customary to transfer such images taken from men to God, in accommodation to our infirmity. By this ascription of praise the Psalmist effectually disposes of all the absurd ideas which have been broached, tending to deny or disparage the power of God, and declares, upon the matter, that God may sooner cease to be, than to sit upon his throne in the government of this world.

Thy throne is established of old - Whatever might occur, the throne of God was firm. That could not be moved. It had been set up from all eternity. It had stood through all the convulsions and changes which had occurred in the universe; and it would stand firm forever. Whatever might change, that was immovable; and as long as that is unchanged we have a ground of security and hope. Should "that" be moved, all would be gone. The margin here is, as in Hebrew, "from then:" but it means "of old;" from the most ancient times; that is, from the period indicated by the next clause, "from everlasting."
Thou art from everlasting - From all eternity; thou hast always existed; thou art ever the same Psalm 90:1.

Thy throne is established of old - There never was a time in which God did not reign, in which he was not a supreme and absolute Monarch; for he is from everlasting. There never was a time in which he was not; there never can be a period in which he shall cease to exist.

Thy (b) throne [is] established of old: thou [art] from everlasting.
(b) In which you sit and govern the world.

Thy throne is established of old,.... Or "prepared from eternity" (b); Christ was set up and anointed as King from everlasting; he had a kingdom appointed and prepared for him so early; and his throne, which is prepared in the heavens, is an established one; it is for ever and ever; his kingdom is an everlasting kingdom; of his government, and the increase of it, there is no end:
thou art from everlasting; as a divine Person, as God, and the Son of God; or he could not have been anointed unto or invested with the kingly office so early; nor have had a glory with his Father before the world began: his eternal existence, as God, accounts for the establishment of his throne of old, without which it could not be.
(b) "paratum", Pagninus, Montanus; "a principio", Targum; "ab antiquo", Syr. "ab aeterno", Gejerus; so Ainsworth.

His underived power exceeds the most sublime exhibitions of the most powerful objects in nature (Psalm 89:9).