7. εἶπεν οὖν. Jesus therefore said again. Because they did not understand He went through it again, explaining the main features.
ἀμὴν ἀμ. This is the important point: the one Door, through which both sheep and shepherds enter, is Christ. Ἐγώ is very emphatic; I (and no other) am the Door: comp. ‘I am the Way’ (Joh 14:6). For ἐγώ εἰμι see on Joh 6:35.
ἡ θ. τ. προβάτων. The Door for the sheep (Joh 10:9) and also the Door to the sheep (Joh 10:1-2). Sheep and shepherds have one and the same Door. The elect enter the Church through Christ; the ministers who would visit them must receive their commission from Christ. Jesus does not say ἡ θ. τ. αὐλῆς, but ἡ θ. τ. προβάτων. The fold has no meaning apart from the sheep.