1 Kings 20:20 - Ellicott's Commentary On The Whole Bible

And they slew... — The attack of this handful of men, supported by a sally of the whole garrison, is not unlike the slaughter of the Philistine garrison and host in the days of Saul (1 Samuel 14), or the still earlier rout of the army of Midian by the night attack of Gideon (Judges 7:16-23). Probably, as in these cases, the Israelites may have risen from various lurking-places to join in the pursuit and slaughter. It does not necessarily follow that the event was miraculous. Such dispersions of vast Oriental armies are not uncommon in history. The lesson is that drawn with noble simplicity by Jonathan: “There is no restraint to the Lord to save by many or by few” (1 Samuel 14:6).