εἰ μὴ ἦλθον καὶ ἐλάλησα αὐτοῖς, ἁμαρτίαν οὐκ εἶχον → if I had not come and spoken to them, they would not be guilty of sin
begin (with solemnities): P. and V. κατάρχεσθαι (gen.).
introduce, initiate: Ar. and P. εἰσηγεῖσθαι.