A.T. Robertson Commentary John 6:52

"The Jews therefore strove one with another, saying, How can this man give us his flesh to eat?" — John 6:52 (ASV)

Strove (εμαχοντο). Imperfect (inchoative) middle of μαχομα, to fight in armed combat (Acts 7:26), then to wage a war of words as here and 2 Timothy 2:24. They were already murmuring (41), now they began bitter strife with one another over the last words of Jesus (43-51), some probably seeing a spiritual meaning in them. There was division of opinion about Jesus in Jerusalem also later (7:12,40; 9:16; 10:19).

How can? (Πως δυναται; ). The very idiom used by Nicodemus in 3:4,9. Here scornful disbelief.

This man (ουτος). Contemptuous use pictured in verse 42.

His flesh to eat (την σαρκα αυτου φαγειν). As if we were cannibals! Some MSS. do not have αυτου, but the meaning is clear. The mystical appropriation of Christ by the believer (Galatians 2:20; Ephesians 3:17) they could not comprehend, though some apparently were against this literal interpretation of "flesh" (σαρξ).