1 Samuel 13
Saul assembles an army to fight the Philistines (an ongoing threat that becomes the crisis of his reign) and waits at Gilgal for Samuel to offer a burnt offering before battle (13:8), but Samuel delays, and Saul, seeing his forces beginning to scatter, offers the sacrifice himself—a transgression of the priestly role that belongs to Samuel (13:11-12). Samuel arrives and condemns Saul: 'You have not kept the command of the LORD your God' (13:13), and prophesies that the kingdom will not endure: 'The LORD has sought for himself a man after his own heart...and the LORD has commanded him to be leader over his people' (13:14). The chapter introduces David (though only by reference) as the one whom the LORD has chosen in Saul's stead, suggesting that Saul's transgression—his impatient seizure of priestly authority—has triggered the fatal rupture between him and the LORD. The Philistines maintain military superiority (13:19-22, they hold the monopoly on iron working), and Israel is outnumbered and poorly equipped, suggesting that human strength alone cannot overcome the covenant enemy without the direct blessing of the LORD, which Saul's disobedience has forfeited.
1 Samuel 13:6
And when the men of Israel saw that they were in straits, (for the people were distressed,) then the people hid themselves in caves, and in thickets, and in rocks, and in high places, and in pits — the Israelites, seeing the overwhelming Philistine force and the danger they face ('tzar, straits, distress'), lose courage. They hide in caves, thickets, rocks, high places, and pits—abandoning the assembly at Gilgal.
1 Samuel 13:7
And some of the Hebrews went over Jordan to the land of Gad and Gilead — some Israelites flee eastward across the Jordan to Gad and Gilead, seeking refuge from the Philistine invasion. As for Saul, he was yet in Gilgal, and all the people followed him trembling — Saul remains at Gilgal with the people who have not fled, and they are gripped with fear ('chel, trembling').
1 Samuel 13:1
Saul reigned one year; and when he had reigned two years over Israel — Saul's reign is noted by two different reckonings of duration, which may reflect textual transmission issues or different ways of marking the beginning and establishment of his rule. The brevity of the mention suggests that the focus shifts quickly to his actions rather than his longevity.
1 Samuel 13:2
Then Saul chose him three thousand men of Israel; whereof two thousand were with Saul in Michmash and in the mount of Beth-el, and a thousand were with Jonathan his son in Gibeah of Benjamin — Saul establishes a standing military force (three thousand men, shloshah alafim) to defend Israel against the Philistines. The force is divided: two thousand under Saul at Michmash, and one thousand under his son Jonathan at Gibeah. Jonathan's position indicates Saul's trust in his son and Jonathan's emerging military role.