The exposure of a high-ranking foreign woman reveals the depth of a calculated political and spiritual plot against the Israelites. Identifying her specifically as a Midianite brings a profound and unique hatred to light. While the neighboring Moabites lured the Israelites into sin out of genuine fear, the Midianites had no reason to feel threatened. Their actions were driven by pure hostility [שפתי כהן, ברכת אשר, גור אריה]. This malice was evident in their methods; while Moabite women operated in secret, the Midianite women brazenly offered themselves in public [שפתי כהן]. Her specific identification might even suggest she was the only Midianite woman to act so openly, or perhaps the only princess mingling among the common people [אור החיים].
Her very name hints at deception and tragedy, suggesting that she either lied to her father and acted against his wishes, or that she was destined to bring disaster and slaughter upon her own people [תורה תמימה]. Ultimately, she became the direct cause of the deadly plague that struck the Israelites [שפתי כהן].
Her father, Zur, was a man of immense power who led a vast confederation of nations [הכתב והקבלה]. Midian was divided into five tribal houses, and Zur was the leader of the largest and most prominent among them [רש"י, אבן עזרא, רש"ר הירש, ביאור שטיינזלץ]. The fact that an entire nation was willing to offer up its own princess for prostitution simply to cause the Israelites to stumble demonstrates a staggering level of hatred [רש"י, רבנו בחיי, שפתי חכמים]. To persuade the other women of his nation to engage in such acts, Zur had to set a personal example, deliberately degrading his own honor and that of his daughter [תורה תמימה, שפתי כהן].
Because of this shameful behavior, Zur suffered a deliberate fall from grace. When the five kings of Midian are listed later on, he is placed third. This exact middle position was chosen to distance him as much as possible from the title of "king" mentioned at the beginning and end of the list [רש"י, יריעות שלמה, גור אריה, משכיל לדוד, דברי דוד]. Yet, while his stature was diminished in the eyes of God, he remained a respected leader among his own people, as Midianite society saw absolutely nothing wrong with his actions [אלשיך]. Another perspective suggests that Zur was actually Balak, the king of Moab, who had lost his royal position there and simply returned to his original rank in Midian [אור החיים].
Beyond exposing the wickedness of Midian, detailing the royal lineage of this woman serves to magnify the bravery of Phinehas. By striking down a foreign princess, he knowingly placed himself in severe political danger. His unhesitating zeal for God in the face of this risk required God to step in and guarantee him a covenant of peace and protection [רש"ר הירש, דעת זקנים, בכור שור, מלבי"ם]. However, some argue that the primary focus remains on the condemnation of Midian rather than the bravery of Phinehas, noting that he had far less reason to fear a foreign princess than he did an Israelite tribal leader [מזרחי, שפתי חכמים].