Albert Barnes Commentary Jeremiah 41:8

"But ten men were found among them that said unto Ishmael, Slay us not; for we have stores hidden in the field, of wheat, and of barley, and of oil, and of honey. So he forbare, and slew them not among their brethren." — Jeremiah 41:8 (ASV)

Treasures - Hidden stores, which would be of great value to Ishmael in his retreat back to Baalis.