προσκαινουργέω
From LSJ
ἀμήχανον δὲ παντὸς ἀνδρὸς ἐκμαθεῖν ψυχήν τε καὶ φρόνημα καὶ γνώμην, πρὶν ἂν ἀρχαῖς τε καὶ νόμοισιν ἐντριβὴς φανῇ → hard it is to learn the mind of any mortal or the heart, 'till he be tried in chief authority | it is impossible to know fully any man's character, will, or judgment, until he has been proved by the test of rule and law-giving
English (LSJ)
work some new thing, πολλά J.AJ17.11.2.
Greek (Liddell-Scott)
προσκαινουργέω: ἐργάζομαι νέον τι κακόν, Ἰωσήπ. Ἰουδ. Ἀρχ. 17. 11, 2.