fidem habere alicui

Etymology:

• fides has six principal meanings. A. subjectively—(1) in an active sense, belief, confidence, which some one holds; (2) passive, veracity, credit which one enjoys; (3) neutral, good faith, sincerity, loyalty, conscientiousness, and especially of the protection which one expects by appealing to a man's loyalty. B. (4) active, ratification, sanction; (5) passive, the thing promised, surety, guarantee; (6) neutral, authenticity, certitude, truth of a thing. Cf. Haacke, Lat Stil. 40-41.