And the priest said, The sword of Goliath the Philistine, whom thou slewest in the valley of Elah, behold, it is here wrapped in a cloth behind the ephod: if thou wilt take that, take it: for there is no other save that here. And David said, There is none like that; give it me.
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
And the priest said, the sword of Goliath the Philistine, whom thou slewest in the valley of Elah,.... See Sa1 17:2, behold, it is here wrapped in a cloth behind the ephod; the garment of the high priest, in which were the Urim and Thummim, and the breastplate, or the linen vestments of the priests; see Sa1 22:18; which were laid up in a chamber...
HE TAKES GOLIATH'S SWORD. (Sa1 21:9) sword of Goliath--(See on Sa1 17:54). behind the ephod--in the place allowed for keeping the sacred vestments, of which the ephod is mentioned as the chief. The giant's sword was deposited in that safe custody as a memorial of the divine goodness in delivering Israel.