The symbolic nature of the sacrament is reemphasized for the benefit of those who were not present on the previous day. This is symbolic of living nourishment, truly a Tree of Life that provides eternal nourishment and life.
Reference: The English text owes its form to a New Testament passage:
John 6:35
35 And Jesus said unto them, I am the bread of life: he that cometh to me shall never hunger; and he that believeth on me shall never thirst.