6:51–58 Jesus’ hearers continue to misunderstand His statements, taking them on a purely physical level (cf. v. 34). Understood literally, what Jesus said would be highly objectionable since it would involve cannibalism and a use of blood that was strictly forbidden in the Law (Gen. 9:4; Lev. 7:26, 27; 17:10–14; Deut. 12:23, 24). Jesus uses the language of eating and drinking to illustrate the intimacy of the union between Christ and the believer. This spiritual union, by which Christ imparts new life to the believer, is portrayed later in the Gospel as the union of a vine and its branches (15:1–8). It is sometimes called the “mystical union,” and is a recurrent topic in Paul’s letters (Gal. 2:20; Eph. 1:3–14).

Though some see here a reference to the Lord’s Supper, a mention of that sacrament at this point would have been incomprehensible to Jesus’ listeners. This passage is best understood as pointing to the spiritual reality the Lord’s Supper also signifies—union with Christ and all the benefits of salvation received through Him.