πρὸς καιρόν
From LSJ
Μηκέθ᾽ ὅλως περὶ τοῦ οἷόν τινα εἶναι τὸν ἀγαθὸν ἄνδρα διαλέγεσθαι, ἀλλὰ εἶναι τοιοῦτον. → Waste no more time arguing what a good man should be. Be one.
Greek > English (Woodhouse)
early, at the right moment, in the nick of time, to good purpose