Gregory the Great
Catena Aurea · Johannesevangelium 21
Jesus saith unto them, Come and dine. And none of the disciples durst ask him, Who art thou? knowing that it was the Lord. Jesus then cometh, and taketh bread, and giveth them, and fish likewise. This is now the third time that Jesus shewed himself to his disciples, after that he was risen from the dead. And none of His disciples durst ask Him, who art Thou? knowing that it was the Lord.
(Hom. xxiv.) By holding this last feast with seven disciples, he declares that they only who are full of the sevenfold grace of the Holy Spirit, shall be with Him in the eternal feast. Time also is reckoned by periods of seven days, and perfection is often designated by the number seven. They therefore feast upon the presence of the Truth in that last banquet, who now strive for perfection.