Charles Ellicott Commentary John 6:63

"It is the spirit that giveth life; the flesh profiteth nothing: the words that I have spoken unto you are spirit, are are life." — John 6:63 (ASV)

It is the spirit that quickeneth.—The word "quickeneth," though it has almost passed from everyday use, will likely still hold its place in theological language and, for the most part, convey the true meaning. If it is retained here, it must, however, be noted that it is a compound of the word rendered "life" at the end of the verse. The essential meaning is: "It is the Spirit that gives life... the words... are spirit and are life."

These words are immediately connected with the idea of the Ascension, which was to precede the gift of the Spirit (John 16:7 and following). We are to find in them, therefore, a deeper meaning than the ordinary one that His teaching is to be understood not carnally, but spiritually.

They think of a physical eating of His flesh, and this offends them. But what if they, who have thought of bread descending from heaven, see His body ascending into heaven? They will then know that He cannot have meant this.

And the Descent of the Spirit will follow the Ascension of the Son. Then, those full of the Holy Spirit will have all these words brought to their remembrance (John 14:26), and they will know what the true feeding on Him is. These very words which He has spoken will carry their lessons to the inmost being and be realized, not simply in a spiritual sense, but as spirit and as life.