'Old' in the Bible

I once was young and now I am old, but I have not seen a righteous person forsaken or his descendants begging for bread.

Don't throw me away when I am old; do not abandon me when my strength fails.

Also, when I reach old age and have gray hair, God, do not forsake me, until I have declared your power to this generation and your might to the next one.

Where is your gracious love of old, Lord, that in your faithfulness you promised to David?

They will still bear fruit even in old age; they will be luxuriant and green.