Psalm 90

The most ancient of the Psalms. There are 2 other songs of Moses (Exodus15, Deuteronomy32). This prayer of Moses was written during the wilderness years on the way to Canaan. In all those years Israel lived in constant need of refuge, shelter, and protection. More than their tents and their armies, Israel had God as their ‘dwelling place,’ their refuge and their protection. The psalm begins with this great affirmation concerning the relation of man to God. Addressing Him, not as Elohim the Mighty One, nor as Yahweh, the Helper, but as Adonai, the Sovereign Lord. Moses declares that He has been the dwelling-place, the habitation, the home of man in all generations – forever. The word ‘dwelling place’ can also be translated ‘refuge’, which is how it is translated in Deut33:27

V2 acknowledges it was God who ‘formed the earth and the world’. Before anything existed, God was from eternity past to eternity future (everlasting to everlasting), He exists, independent of all His creation. 
The command of v3 is an echo of Gen3:19; experience before our eyes make it clear how all men, even the wisest, the strongest, the greatest, and the mightiest monarchs and princes in the world are but men, made of red earth, and quickly turn again to dust. 
Having introduced the idea of God’s eternal being, living outside of time with no beginning or end, Moses poetically repeated the idea (v4-6). For the eternal God, a ‘thousand years’ seems like a single day, and a single day in the ‘past,’ not the present.

Moses used many poetic pictures to describe God and time. In God’s sight, a thousand years was like yesterday, like a watch in the night, like a flood, like a night of sleep. He added this picture: a thousand years is like grass which ‘grows up’ in the ‘morning’ and in ‘the evening it is cut down and withers.’ God’s perspective of time’s passing is very different from ours. God is outside time. Jesus was the eternal God stepping within the bounds of time – a mountain that felt the footsteps of its creator and there saw Him lifted on a rough-hewn cross between heaven and earth as if He were not fit for either.