to be ἀδύνατος, lack strength, Epich. 266, Arist. Somn.Vig. 454a27: c. inf., to be unable to do, Hp. de Arte 7, Pl. R. 366d, X. Mem. 1.2.23, Arist. EN 1165b22, Pol. 1287b17, etc.
of things, to be impossible, LXX Jb. 10.13, Phld. Ir. p.98 W., Ev.Matt. 17.20, Ev.Luc. 1.37, Ps.-Callisth. 3.26.