What does John 6:56 mean?

Jesus has greatly offended the people who came to find Him in Capernaum (John 6:52). Christ explained that He was the "true bread from Heaven" (John 6:32–33). This meant that only those who believed in Him (John 3:36), as the One sent from God, could see eternal life (John 6:40). This was part of Jesus' teaching to focus less on material things and more on heavenly things. The people were unhappy with the idea that belief, and not good deeds, was the real key to salvation (John 6:27–29). When Jesus expands the analogy to say that His flesh is this Bread of Life, they are outraged (John 6:51–52).

Jesus uses the term "abide" here, from the Greek root word menō, meaning "to continue, to dwell, or to endure." This sense of "abiding" is used in reference to the relationship between God the Father and God the Son (John 14:10), God the Son and God the Spirit (John 1:32), as well as to the relationship between Jesus and those who are saved (John 15:4).

Most of the people present in Capernaum mistake Jesus' claim in a crass, physical way. They think this is a reference to cannibalism (Genesis 9:3–4; Leviticus 17:10–16). Others grasp that He is speaking in some form of parable or metaphor, but still find it hard to accept (John 6:41–42). Many of those who were following Jesus to this point will react by abandoning Him (John 6:66). However, Jesus is tying this idea together with the comments He has already made about eternal life. He pointed out that belief in Him granted a person life. Later, Jesus will explicitly say that His use of these words is symbolic, not a reference to eating His literal, physical flesh and blood (John 6:63).