Discourse on the Bread of Life. As in John 4 Jesus is the giver of 'living water,' so here He is the 'living bread' or 'manna' of the soul. Such language had been to some extent prepared for by OT. references to the spiritual feast to which 'Wisdom' invites her children, 'Come eat ye of my bread, and drink of the wine which I have mingled' (Proverbs 9:5, etc.); and by the current view that the 'manna' of the OT. is to be spiritually interpreted (Philo identifies it with the 'Logos' or 'Word' of God; St. Paul calls it 'spiritual meat,' 1 Corinthians 10:3 the Psalmist calls it 'angels' food,' Psalms 78:25). There are also OT. references to the banquet of the Messiah (Isaiah 25:6, etc.), which are frequently echoed in the NT. (Matthew 8:11; Matthew 22:2.; Matthew 25:10; Matthew 26:29; Luke 14:15; Revelation 19:9). But such passages do not lead up to, or explain our Lord's language about eating His flesh, and drinking His blood. The nearest parallel to this is the Passover. Our Lord's hearers were about to go up to Jerusalem to eat the Passover (John 6:4). Some of them, perhaps, had heard the Baptist call Him 'the Lamb of God that taketh away the sin of the world' (John 1:29; John 1:36). Our Lord, accordingly, set before them His Person as the sacred reality of which the Passover lamb was a type. As the blood of the Paschal lamb had protected the Israelites of old from the sword of the destroying angel, so the death of the Lamb of God would give spiritual life to the whole world (John 6:51). As in the Paschal meal the Israelites ate the flesh of a literal lamb, so in the feast which He came to prepare, they would spiritually eat the flesh and drink the blood of the True Lamb. By the 'flesh' of Christ is to be understood His human nature (see John 1:14), and by His blood, His atoning blood, shed for the sins of the world. There is reference, therefore, both to the Incarnation, and to the Atonement. The eating and drinking of Christ's flesh and blood is spiritual (John 6:63), and can only take place through the medium of faith (John 6:35; John 6:40; John 6:47). It is not, however, identical with faith, but rather is the reward of faith. Those who have lively faith in Christ as the Son of God and the Redeemer of the world, are so incorporated with Him, that they dwell in Him and He in them (John 6:56); He is in them a principle of spiritual life (John 6:57), and of resurrection (John 6:54); and He strengthens and refreshes their souls, so that they neither hunger nor thirst (John 6:35; John 6:55), until they attain everlasting life (John 6:50-51; John 6:54; John 6:58). This vital union between Christ and the believer is elsewhere illustrated by the parable of the True Vine (John 15:1.), and by St. Paul's metaphor of the body and the members (1 Corinthians 12:12.).
This discourse is regarded by nearly all commentators as intended to prepare the way for the institution of the Lord's Supper, by explaining the fundamental idea and principle of that holy rite, viz. the union of the believer with Christ's human nature through faith. The Supper was ordained (see on Matthew 26:26-30) as the ordinary and covenanted means of feeding upon Christ—of 'eating his flesh and drinking his blood,' i.e. of appropriating spiritually and by faith His glorified humanity and sharing in the benefits of His passion. This, the original apostolic doctrine, which guarded both the reality of the reception by the believing soul of Christ's true humanity, in this ordinance, and also the absolute need of a lively faith if this blessed result was to be achieved, was endangered in St. John's time by two opposite tendencies, that of Gnosticism, which, while confessing Christ's Godhead, denied His Incarnation and Atonement, and that of a false ecclesiasticism, which, while confessing both, imagined that union with the Incarnate Redeemer could be attained mechanically through the sacraments, without a living faith. As against the former the evangelist emphasises the reality of Christ's 'flesh,' or human nature, and of His 'blood' or atoning sacrifice; and as against the latter the need of a living faith, as the only means through which Christ's flesh and blood can be savingly appropriated, and become the food of the soul. The 'flesh' of Christ, which is received by faith, is, of course, His glorified humanity, as it now is at the right hand of God, and as it is communicated to believers through the Spirit (John 6:62-63). At the institution of the Supper, however, our Lord spoke not of His 'flesh,' but of His 'body,' and for this there was a reason. Both words denote Christ's human nature, but whereas to eat Christ's 'flesh' indicates only the union of the individual believer with his Saviour, to eat Christ's 'body' indicates also his union with other believers, a fundamental idea of the sacrament of love, which was intended to be the centre of Christian unity (1 Corinthians 10:16-17).