ἐν τῷ δέοντι
From LSJ
Θνητὸς πεφυκὼς τοὐπίσω πειρῶ βλέπειν → Homo natus id, quod instat, ut videas, age → Als sterblich Wesen mühe dich zu seh'n, was folgt
Greek > English (Woodhouse)
early, at the right moment, in the nick of time, in time of need