en_tn/psa/136/008.md

to rule by day ... to rule by night

The sun, moon, and stars are spoken of as if they were kings. Alternate translation: "to mark the time of day ... to mark the time of night" (See: rc://en/ta/man/translate/figs-metaphor and rc://en/ta/man/translate/figs-personification)

for his covenant faithfulness endures forever

The abstract noun "faithfulness" can be translated with an adjective. See how you translated this in Psalms 136:1. Alternate translation: "because he remains faithful to his covenant forever" (See: rc://en/ta/man/translate/figs-abstractnouns)