When he was grown up (μεγας γενομενος). "Having become great" (from Exodus 2:11).

Refused (ηρνεσατο). First aorist middle indicative of αρνεομα, to deny, to refuse. He was of age and made his choice not from ignorance.

Son (υιος). Predicate nominative with λεγεσθα (to be spoken of, present passive infinitive, of λεγω).