Charles Ellicott Commentary 1 Samuel 14:20

"And Saul and all the people that were with him were gathered together, and came to the battle: and, behold, every man`s sword was against his fellow, [and there was] a very great discomfiture." — 1 Samuel 14:20 (ASV)

Assembled themselves. —In the margin of the English Version, we find “were cried together,” that is, “were assembled by the trumpet call.” The Syriac and Vulgate, however, more accurately render the Hebrew shouted, that is, raised the war-cry of Israel.

Every man’s sword was against his fellow.— The statement in the next verse (1 Samuel 14:21) explains this. Profiting by the wild confusion that then reigned throughout the Philistine host, a portion of their own auxiliaries—unwilling allies, doubtless—turned their arms against their employers or masters. From this moment no one in the panic-stricken army could rightly distinguish friend from foe. In such a scene of confusion the charge of Saul, at the head of his small but well-trained soldierly band, must have done terrible execution. Shouting the well-known war-cry of Benjamin, it penetrated wedge-like into the heart of the broken Philistine host.