Psalms 90:4
Psalms 90:44For in Your sight a thousand years are but a day that passes, or a watch of the night.
Cited alongside to explain why long periods are no difficulty for Jehovah, and historically used in Watchtower chronological reasoning where prophetic days and years are equated. The general application is that apparent delay reflects human impatience rather than any failure on God's part.
Read the psalm around the verse. Moses is contrasting God's permanence with human brevity — verse 3 has people returning to dust, verse 5 sweeps them away like sleep, verse 10 gives seventy years, eighty if strong. The thousand-years-as-a-day line is one image in a meditation on how short a life is against a God who has no beginning. It is not a unit of measurement, and taking it as one produces arithmetic the psalm shows no interest in. Verse 12 gives the application Moses actually draws: teach us to number our days, that we may gain a heart of wisdom. The point is to make us take our own short lives seriously, not to make long delays weightless. That inverts the usual use. Psalm 90 says: your time is brief, so pay attention now. Which lands close to — now is the day of salvation. Compare , .