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.

Jesus has just fed the people with physical bread not long ago, and the people desired more the next day. When Jesus told them He was the bread of life, they were disappointed. How often do we get disappointed when we need a solution to our daily problems and we were told to pray about it? We feel we need something more logical, right? (Human philosophy) nothing can be more logical than the word of God to a man with spiritual understanding.

The bread is relevant for life bodily and likewise the word of God(Jesus) is relevant for life spiritually. "Matt 4:4 - But he answered and said, It is written, Man shall not live by bread alone, but by every word that proceedeth out of the mouth of God."  Man is a spirit being, so we tend to live by words, this is the reason many people live by other men's philosophy. "Hebrews 11:3

Through faith we understand that the worlds were framed by the word of God, so that things which are seen were not made of things which do appear."