Charles Spurgeon Commentary John 6:57-58

"As the living Father sent me, and I live because of the Father; so he that eateth me, he also shall live because of me. This is the bread which came down out of heaven: not as the fathers ate, and died; he that eateth this bread shall live for ever." — John 6:57-58 (ASV)

As the living Father hath sent me, and I live by the Father: so he that eateth me, even he shall live by me. This is that bread which came down from heaven: not as your fathers did eat manna, and are dead: he that eateth of this bread shall live for ever.

This is spiritual feeding upon spiritual truth.