It's a futile effort on the part of human beings to set up their works against God's grace. "Work-righteousness" is a major problem not only in many false religions but also in many Christian denominations. The people in our gospel text quickly fall into the false premise of earning eternal bread with their works! With their blinders on, they were even prepared to do the works of God! They wanted to trust their senses so that they could see and believe. Jesus carefully but patiently changes the perspective of His listeners. He teaches them that giving eternal bread is the work of God. The correct direction is from above to below (from God to man). Not from below to above (from man to God). After all, who can dare to earn a tiny morsel of eternal bread from the table of God's grace? The emphatic statement of Jesus that He was the bread of life explains it all. The eternal bread had to be given away freely to all people without cost. The Bread of life is not for sale, but completely free! Not by works, but by grace alone! Amen.