Then David came to Nob, to Ahimelech the priest. And Ahimelech came to meet David, trembling, and said to him, “Why are you alone, and no one with you?”
Here, I. David, in distress, flies in the tabernacle of God, now pitched at Nob, supposed to be a city in the tribe of Benjamin. Since Shiloh was forsaken, the tabernacle was often removed, though the ark still remained at Kirjath-jearim. Hither David came in his flight from Saul's fury (Sa1 21:1), and applied to Ahimelech the priest. Samuel the prophet could not protect him, Jonathan the prince could not.
Commenting on 1 Samuel 21:1-9
Then came David to Nob, to Ahimelech the priest,.... The high priest, as Abarbinel rightly calls him; he was the brother of Ahijah, the son of Ahitub, who being dead he succeeded him; though some say (a) he was the same; see Sa1 14:3; who was now at Nob, the tabernacle being there, whither probably it was removed by Saul, and where and at Gibeon...
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? (a) Where the ark then was to ask counsel of the Lord.