drew water … poured it out: This ceremony is not mentioned elsewhere in the Old Testament.
Sometimes, Israelites fasted (did not eat) to show grief or seek the Lord’s favor (2 Samuel 1:12; 12:22–23; 1 Kings 21:27; Ezra 8:21–23; Nehemiah 9:1; Esther 4:3, 16; Joel 2:12; compare Luke 2:37; Acts 13:2–3; 14:23).
Having Samuel as Israel’s judge was refreshing compared to Eli’s poor leadership (see 1 Samuel 4:18 and 1 Samuel 4:18) and the leadership of some other judges, for example:
Gideon (Judges 8:22–27)
Jephthah (Judges 11:30–12:7)
Samson (Judges 13:1–16:21)