τῷ στενῶ τῆς προθεσμίας. ἡ προθεσμία sc. ἡμέρα was in Attic Law a day fixed beforehand before which money must be paid, actions brought, etc.  cf. Plat. Legg, 954, D.  It is the “time appointed” of the Father in Gal. iv. 2.