1 Samuel 14:11-14

11So both of them showed themselves to the garrison of the Philistines. And the Philistines said, “Look, the Hebrews are coming out of the holes where they have hidden.”

12Then the men of the garrison called to Jonathan and his armorbearer, and said, “Come up to us, and we will show you something.” Jonathan said to his armorbearer, “Come up after me, for the Lord has delivered them into the hand of Israel.”

13And Jonathan climbed up on his hands and knees with his armorbearer after him; and they fell before Jonathan. And as he came after him, his armorbearer killed them.

14That first slaughter which Jonathan and his armorbearer made was about twenty men within about half an acre of land.