διαπιστεύω · diapisteuō — LSJ
entrust to one in confidence, τινὶ τὴν πόλιν, τὴν δυναστείαν, Aeschin. 3.8, Plb. 5.40.7; τῷ θεῷ τὰν ὠνάν Rüsch Grammatik der delph.Inschr.p.326 (ii B.C.); also δ. τινὶ περί τινος Aeschin. 1.188.
believe thoroughly, τι Arist. PA 673a17, cf. Max.Tyr. 10.7.
c. dat., have confidence in, believe, PHib. 1.147 (iii B.C.):— Pass., to be trusted or believed, D. 10.51, Aen.Gaz. Thphr. p.18B.