What does psalm 90 mean?

Footnotes:a.Psalm 90:10 This psalm is credited to Moses, who is interceding with God to remove the curse which made it necessary for every Israelite over twenty years of age (when they rebelled against God at Kadesh-barnea) to die before reaching the promised land (Num. 14:26-35). Moses says most of them are dying at seventy years of age. This number has often been mistaken as a set span of life for all mankind. It was not intended to refer to anyone except those Israelites under the curse during that particular forty years. Seventy years never has been the average span of life for humanity. When Jacob, the father of the twelve tribes, had reached 130 years (Gen. 47:9), he complained that he had not attained to the years of his immediate ancestors. In fact, Moses himself lived to be 120 years old, Aaron 123, Miriam several years older, and Joshua 110 years of age. Note as well that in the Millennium a person dying at 100 will still be thought a child (Isa. 65:20).