Jesus’ teachings as revealed in John 6:30-58 were difficult; they left the Jews who were listening to Him aghast, and many of His own disciples no longer followed Him afterward (John 6:60, 66). Their reaction is completely understandable: after all, Jesus has just said that they need to eat His body and drink His blood in order to obtain eternal life (John 6:55-56)! Was Jesus asking the Jews to practice cannibalism? What could He possibly mean by saying such things?
Many look at John 6:30-38 and conclude that Jesus is speaking of the Lord’s Supper. It is true that Jesus will identify the bread as His body and the cup as His blood and command His followers to partake of that Supper (cf. Matthew 26:26-28, 1 Corinthians 11:23-26). Jesus’ death and resurrection also provide the opportunity to have eternal life, in that sense, they do help to sustain our existence spiritually (cf. Romans 6:3-7).
When Jesus speaks to the Jews in John 6, however, the Lord’s Supper is still in the future. Jesus is telling the Jews presently that they must eat of His body and drink of His blood in order to obtain eternal life (John 6:53-58). The Lord’s Supper, therefore, is not primarily in view in John 6:30-58. In order to understand what Jesus is saying, we must understand Jesus’ referent.
The Jews asked Him for a sign and indicated that their fathers were given manna from Heaven (John 6:30-31). Jesus then demonstrates that God gave them the bread from Heaven, and the bread that God sends from Heaven provides life (John 6:32-33). Jesus points out that He is the bread from Heaven, and that is why people must eat of His body and drink of His blood to obtain eternal life (John 6:35, 48-58).
This whole discussion is based in Moses’ statement in Deuteronomy 8:3:
“And he humbled thee, and suffered thee to hunger, and fed thee with manna, which thou knewest not, neither did thy fathers know; that he might make thee know that man doth not live by bread only, but by everything that proceedeth out of the mouth of the LORD doth man live.”
Manna from Heaven was designed to point Israel to the life-giving and life-sustaining words that come from the mouth of God. God gave them the physical bread to depend on Him and His words, the spiritual and life-giving “bread.”
As Jesus demonstrates, those who ate the manna died (John 6:49). The only way to live eternally is to live upon “that which proceeds from the mouth of God.” And who does John declare Jesus to be in John 1:1, 14? The Word of God made flesh!
Jesus is not asking the Jews to become cannibals. Instead, He uses very stark terms to teach them and us that we can only obtain eternal life by feasting upon the Word of God, the message made manifest through the life, death, and resurrection of Jesus (John 1:18, 14:6-12). Our lives must be sustained by the Word, both by what is revealed in Scripture and by following in the steps of Jesus the Incarnate Word (2 Timothy 3:16-17, 1 Corinthians 11:1, 1 John 2:6). Let us “eat the flesh” and “drink the blood” of the Incarnate Word: let us learn of God through Jesus and the Scriptures and do His will today!