It is the spirit who gives life. The flesh profits nothing. The words that I speak to you are spirit, and are life.
They murmur that His saying is hard, unwilling to ask Him humbly to explain it. If they had begged of Christ to declare this parable, He would have opened it to them; but they will not have His sayings explained, because they would lose their pretext for rejecting them.
AI summary
Commenting on John 6:60-71
To convince the Jews that our Saviour did not mean a carnal and fleshly eating of his body, he tells them, That such an eating would profit nothing; but it is a spiritual eating of him by faith, that bringeth that quickening life of which he had spoken.
Verse 63. It is the Spirit that quickeneth. These words have been understood in different ways. The word "Spirit," here, evidently does not refer to the Holy Ghost, for he adds, "The words that I speak unto you, they are spirit." He refers here, probably, to the doctrine which he had been teaching in opposition to their notions and desires.