We thus see that the Present Participle (φωτιζόμενοι) describes a process of gradual illumination during the course of instruction, to be completed in Baptism, a sense which is well expressed in the Latin Gerundive “Illuminandi.”  And as we have seen that the candidates are addressed as οἱ φωτιζόμενοι even before the course of instruction has commenced, the quasi-Future sense “follows necessarily from the context Cf. Winer, Grammar of N.T. Greek, Sect. xl. 22, note 3..”