I Samuel 14:15–23: Israel Routes the Philistines
In the last passage, Jonathan and his armour-bearer attacked and defeated a Philistine outpost, and killed a bunch of Philistines. This passage continues on from there.
Because of the attack on their outpost, the entire Philistine army gets into a panic—a panic which is sent by God (verse 15), and is so bad that the ground shakes. Saul has some lookouts watching the Philistines, and they see all of the commotion, and the Philistine army “melting away in all directions” (verse 16). Saul doesn’t know what’s going on, so he has his troops gathered, looks to see who is missing, and finds that Jonathan and his armour-bearer are gone.
Saul still doesn’t seem to be sure what to do, though, because he then commands the priest to bring the Ark—but even as he is speaking to the priest, the “tumult” (verse 19) is increasing more and more, so he tells the priest to withdraw his hand (a figure of speech?), and instead just summons his men to go into battle.
When the Israelites go into battle, they find the Philistines in total confusion. So badly confused that they’re actually striking each other with their swords! This passage also tells us that there have been some Israelites with the Philistines, but they now rejoin the Israelites, as do all of the Israelites that had previously deserted the army.
So the LORD uses all of these Israelites to rescue Israel, and the battle continues on. It will still be going on when we get to the next passage.
Saul seems to be hesitating to attack the Philistines, and my guess is that it’s fear which is stopping him. (That may not be the most insightful thing I’ve ever said, but the text doesn’t specifically say that he’s scared, so it has to be an inference.) Jonathan seems to be the hero here, not Saul.