Wrapped in a cloth behind the ephod - Rather, “in the cloak,” Goliath’s military cloak, which was part of the dedicated trophy. The ephod was naturally hung up where the high priest alone could get at it.
Related Commentaries of 1 Samuel 21:9
1 Samuel 21:9
9 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.