Now the Hebrews who were with the Philistines as before, and who went up with them into the camp, [from the country] round about, even they also [turned] to be with the Israelites who were with Saul and Jonathan.
Half a furrow of land (1 Samuel 14:14) was half a parcel of land that a yolk of oxen could plow in one day. Evidently God assisted Jonathan by sending a mild earthquake to unnerve the Philistines further (1 Samuel 14:15; cf. Deuteronomy 7:23).