Augustine of Hippo — as excerpted in the Catena Aurea on John 6:60-71

“(Tr. xxvii. 2) Such is our Lord’s discourse. The people did not perceive that it had a deep meaning, or, that grace went along with it: but receiving the matter in their own way, and taking His words in a human sense, understood Him as if He spoke of cutting of the flesh of the Word into pieces, for distribution to those who believed on Him: Many therefore, not of His enemies, but even of His disciples, when they heard this, said, This is an hard saying, who can hear it?”