John 6:60 - Joseph Benson’s Commentary on the Old and New Testaments

Many of his disciples That is, of those who followed him as such; when they had heard this Had heard the above discourse; said, This is a hard saying A strange discourse, a doctrine difficult to be believed. Hard indeed it must have appeared, as it does still appear, to the children of the world, but sweet to the children of God. Scarce ever did our Lord speak more sublimely even to the apostles in private. Who can hear it Who can understand, believe, and obey it? “Most of the metaphors in this discourse (and particularly that of food, to signify doctrine, and of eating and drinking, to signify believing) were abundantly easy, and might have been understood at the very first by the Jews, being found in their Scriptures, and used in their schools. Only, not being able to comprehend what he meant by his flesh, they took the whole literally, and were so offended at the thought of eating his flesh and drinking his blood, a thing not only prohibited by Moses, but repugnant to the customs of all civilized nations, that many of them who were his disciples, when they heard it, said it was absurd.”