This means to think about these things. Alternate translation: "think about these things" or "remember these things" (See: [[rc://en/ta/man/translate/figs-idiom]])
The abstract noun "faithfulness" can be translated with an adjective. Alternate translation: "meditate on the things that Yahweh has done that show that he is faithful to his covenant" (See: [[rc://en/ta/man/translate/figs-abstractnouns]])