{He that hath seen} (ho he(9372)ak(9373)). Perfect active
articular participle of hora(935c). John the Apostle was there and
saw this fact (still sees it, in fact). This personal witness
disproves the theory of the Docetic Gnostics that Jesus did not
have a real human body. {He knoweth} (ekeinos oiden). That is
John does like  9:37 . It is possible that ekeinos may be a
solemn appeal to God as in  1:33  or Christ as in  1Jo 3:5 .
Bernard argues that the final editor is distinguishing the
Beloved Disciple from himself and is endorsing him. But the
example of Josephus (_War_. III. 7, 16) is against this use of
ekeinos. John is rather referring to himself as still alive.