Psalm 90:4 (ESV)

4 For a thousand years in your sight are but as yesterday when it is past, or as a watch in the night.

For God, a thousand years are like a day. From God’s perspective, world history is like mere seconds. Even though the journey from Egypt to Horeb must have seemed like an eternity to the Israelites, for Yahweh their constant discontent seemed like a moment ago! This was the root of his anger. This should also make us think about our unrighteousness and about the sins of our fathers, which are always fresh in his memory.