1 Samuel 21:1
Then came David to Nob to Ahimelech the priest: and Ahimelech was afraid at the meeting of David, and said unto him, Why art thou alone, and no man with thee? Then came David to Nob to Ahimelech the priest: and Ahimelech was afraid at the meeting of David, and said unto him, Why art thou alone, and no man with thee?
Nob was a Benjaminite city to which the tabernacle had been moved from Shiloh. Ahimelech served there as high priest. David came there in haste, apparently alone, with an anxious and sorrowful face. He was hungry and in need of food.
Ahimelech was afraid and astonished at meeting David and asked why he was alone with no man with him. Fearing discovery, David falsely claimed Saul had sent him on a secret, urgent mission, showing lack of faith in God, and this deception led to the high priest's death. Ahimelech gave David the consecrated shewbread ordinarily reserved for priests, which David shared with his hungry followers.
David's urgent and excessive hunger made his taking of the bread guiltless. Meeting urgent human need in service to God takes precedence over rigid application of ceremonial rules, does not violate God's purpose for sacred service, and shows that exceptional need can make justifiable use of what is ordinarily set apart. The episode supports the right of the disciples to pluck and eat grain on the Sabbath to sustain themselves for God's work. The episode does not excuse careless neglect of the tithe.