en_tn/psa/089/028.md

I will extend my covenant faithfulness to him forever

Yahweh speaks of continuing to act faithfully towards David is spoken of as if Yahweh's covenant faithfulness were an object that he extends or makes longer. The abstract noun "faithfulness" can be translated with an adverb. Alternate translation: "I will continue to act faithfully towards him forever" (See: rc://en/ta/man/translate/figs-metaphor and rc://en/ta/man/translate/figs-abstractnouns)