v1: Eleazar was consecrated as priest to tend the ark. It seems the attitudes of the time of the latter judges persisted, as each one did what was right in their own eyes.
v2-4: For a further twenty years, the people mourned, doubtless continuing to suffer at the hands of the Philistines. Samuel's message was uncompromising; they must worship and serve the Lord God only, for He demands total loyalty. This meant to depart from idolatry in all its forms. God would honour their repentance. Samuel did not mention the ark; ultimately this was not the crucial issue. His concern was that the people would get right with God.
The immediate threat was the Philistines, and the Lord's deliverance was the visible sign of His blessing. As a result the people put away their foreign gods.
v5-6: Samuel gathered the people together at Mizpah, for repentance and prayer.
v7-11: While the people were at Mizpah, the Philistines took opportunity to mount a fresh attack. The people, still weak in faith, feared them, and pleaded with Samuel to pray for them. We do notice that they did not depend on the ark, which was at Kiriath Jearim, but they turned to Samuel to pray. God honoured Samuel's prayer and offering.
The people had endured the loss of the ark, the death of Eli, and lack of revelation from God; they now began to return to the true God. Through Samuel, the nation is brought back to God.
v12: Ebenezer was, this time, the testimony to God's help. Samuel had prayed and worshipped, and God had answered, the Philistines were defeated and subdued.
v13-17: The summary of Samuel's ministry. There was a period of peace and stability, as the Philistines and Amorites were subdued. Samuel continued to act as Judge and Priest, touring central Israel.
His life also marked the change from Judges to Kings as leaders over Israel.