Charles Ellicott Commentary 1 Samuel 15:19

"Wherefore then didst thou not obey the voice of Jehovah, but didst fly upon the spoil, and didst that which was evil in the sight of Jehovah?" — 1 Samuel 15:19 (ASV)

Didst fly upon the spoil. —The expression used evidently includes the idea of greedy eagerness, as though Samuel detected a spirit of grasping covetousness at the bottom of this disobedient act of Saul’s.