The Torah gives us some pretty strong clues, and it all boils down to how they chose to attack us.

Think about the story of Balaam and Balak. Remember that? Balak, the King of Moab, hired the prophet Balaam to curse the Israelites. Instead, Balaam wound up blessing them (much to Balak's frustration!). But the story doesn't end there. Balaam, unable to directly harm the Israelites, advised Balak to use a different tactic: seduction.

That brings us to the passage in Bamidbar Rabbah 21, which focuses on the commandment: “Assail the Midianites and smite them” (Numbers 25:17). The text connects this command directly to the incident of Peor, and the story of Kozbi, the Midianite princess. “For they assailed you, with their deceits that they deceived you in the matter of Peor, and in the matter of Kozbi daughter of the prince of Midian, their sister, who was slain on the day of the plague in the matter of Peor” (Numbers 25:18).

The Bamidbar Rabbah asks a crucial question: why this harsh command to "assail" the Midianites? The answer lies in their method of attack. "For they assailed you" – and from here, the Sages deduced a vital principle: "One who comes to kill you, kill him first." Seems pretty straightforward, right? Self-defense.

But Rabbi Shimon takes it a step further. He asks, "From where is it derived that one who causes a person to sin is worse than one who kills him?" His reasoning is powerful: "It is because one who kills, kills in this world, but he has a share in the World to Come, but one who causes him to sin kills him in this world and in the World to Come." In other words, physical death is finite, but spiritual death? That has eternal consequences.

The Bamidbar Rabbah then draws a comparison: Two nations, Egypt and Edom, greeted Israel with the sword. "The enemy said: I will pursue, I will overtake…I will draw my sword" (Exodus 15:9). And, "Edom said to him: You will not pass through me, lest I come out toward you with the sword" (Numbers 20:18). Two other nations, Ammon and Moab, attacked with transgression, leading Israel into sin. The Sifrei Bemidbar 131 even points out that Ammonite women were involved in the harlotry at Shittim.

Now, here's the kicker: Regarding those who attacked with the sword, it is written: "You shall not despise an Edomite…you shall not despise an Egyptian" (Deuteronomy 23:8). There's a possibility of reconciliation, of forgiveness, down the line. But regarding those who used transgression to cause Israel to sin: "An Amonite or a Moavite shall not enter…even the tenth generation…forever" (Deuteronomy 23:4).

The difference is stark. Physical aggression, while terrible, is seen as less damaging in the long run than the insidious act of leading someone astray, corrupting their morals, and severing their connection to the Divine.

So, what's the takeaway? It's not just about physical survival, but about spiritual integrity. The Torah teaches us to guard ourselves not only against those who would harm our bodies, but even more so against those who would corrupt our souls. It’s a powerful reminder that the choices we make, and the influences we allow into our lives, have consequences that extend far beyond this world.