en_tn/psa/091/016.md

will satisfy him with the length of his days

The idiom "the length of his days" here refers to the duration of his life. It may imply a a long life. Alternate translation: "I will satisfy him by giving him a long life" or "I will make him happy by letting him live a very long time" (See: rc://en/ta/man/translate/figs-idiom)

and show him my salvation

"and I will show him my salvation." The psalmist speaks of the work God does to save people as if it were a physical object. Alternate translation: "I will save him so that he knows I am the one who saved him" (See: rc://en/ta/man/translate/figs-metaphor)