Albert Barnes Commentary Psalms 93:2

"Thy throne is established of old: Thou art from everlasting." — Psalms 93:2 (ASV)

Your 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.”

You are from everlasting - From all eternity, you have always existed; you are ever the same (Psalms 90:1).