Great question. Thank you for getting us into the Scriptures. I think the most challenging passages can lead to breakthroughs.
For one, I think it’s important to recognize that “totally destroy” is hyperbolic. As Ronald Youngblood points out in his discussion of the passage, "The description of the total destruction of “all” the people (v. 8) is hyperbolic, since the Amalekites as a whole survived to fight again (cf. 30:1). "
Mary Evans, in her commentary The Message of Samuel, notes:
However, at this point both Saul and the army lost sight of the concept of a God-ordained punishment mission. They destroyed only people and things that were not seen as useful and kept everything that could be of use to them, including the Amalekite king Agag and the best of all the animals. This was not simply an act of disobedience, although of course it was that; it was a direct affront to God, a refusal to take seriously the concept of his holiness and the complete dedication of the Amalekite people and goods to him (87).
The IVP OT Background Commentary points out,
Since the warfare was commanded by Yahweh and represented his judgment on Israel’s enemies, the Israelites were on a divine mission with Yahweh as their commander. Since it was his war, not theirs, and he was the victor, the spoil belonged to him.
Finally, to return to Youngblood,
Saul’s terminology in v. 21 and Samuel’s in v. 22 link the disobedience of Saul and his men to the earlier wickedness of Eli and his reprobate sons. As the latter had sinfully fattened themselves on the “choice parts” of Israel’s offerings (2:29), so Saul’s troops had stubbornly kept the “best” of the plundered animals in order to sacrifice them (v. 21; the Heb. word in the two passages is identical and is not the same as the word for “best” in vv. 9, 15). As the doom of Hophni and Phinehas was sealed because it was the Lord’s “will” to put them to death (2:25), so the rejection of Saul is irreversible because the Lord does not “delight” in willful disobedience (v. 22; the same Heb. root in both verses).
I think this final quote most directly answers your question. In both cases, the sacrificial system’s original intent was twisted for personal benefit in defiance of God’s holiness and purposes.
Here are some points that come to my mind:
First, an apologetic note.
One of the charges against the holy war against people groups in the Canaanites is that this was a self-serving justification. Of course, you said God wanted you to do this - look at how it benefits you!
But intriguingly, we see here that God rejects Saul as king precisely because he turned this divine command into a means of benefitting himself!
Second, it leads me to search my heart.
How do we take God’s commands and use them to benefit ourselves?
Isn’t this one of the root causes behind scandal after scandal in the church?
One point that strikes me about the Hillsong documentary (after the first episode):
The featured church members sincerely practiced the way of Jesus.
The leaders manipulated their sincerity to avoid the way of Jesus.
So for a while, the leaders benefitted from luxury lifestyles on the backs of their depleted followers. But now they are exposed as frauds and cheats. And what does God think of their stewardship of his church?
Third, instead of taking responsibility for our sins, we are prone to blame others.
In this story, a commentary helped me see how in 1 Samuel 15:15, Saul doesn’t take responsibility. Instead, he blames the troops. But if you look at verse 9, it says, “Saul and the troops spared…”
Saul was the king! It is nonsensical for him to state that the troops aren’t under his control and acted separately from his authority. What kind of king doesn’t command his troops?
His lie is obvious. He doesn’t believe what he is saying. Yet he hopes to trick Samuel.
We may think our lies fool God. But he sees through them - and often, so do others.
Finally, we think disobedience is for our benefit, but it contribute to our downfall.
It seems to me that in blaming the troops, Saul seals his punishment. He is admitting to the Lord’s prophet, I’m not really in charge here. And the punishment is: the Lord has rejected you as king (1 Samuel 15:23).
When we fail to obey God, we may think it is to our personal advantage. But this story reveals that is because we are self-deceived. The disobedience sets us on a pathway to lose what God entrusted us.