Psalms 37:18 - Matthew Poole's English Annotations on the Holy Bible

Knoweth; observeth with singular care and affection The days of the upright, i.e. their condition, and all things which do or may befall them, their dangers and fears, and suffering from ungodly men; and therefore will watch over them, and preserve them from all the designs and attempts of their enemies. Days, or years, or times are oft put for things done or events happening in them, as Deuteronomy 32:7 Psalms 31:15, Psalms 77:5 143:5 Isaiah 63:11. Their inheritance shall be for ever; to them and their seed for ever: compare Psalms 37:29. And when they die, their inheritance is not lost, but exchanged for one infinitely better.