שמואל ב, פרק ג׳, פסוק ט׳

A bitter confrontation brings the powerful army commander of the house of Saul to a breaking point. Recognizing his immense political and military strength, Abner makes the dramatic decision to shift his loyalty and transfer the kingdom to David [אלשיך]. He seals this irreversible shift with a severe and absolute oath, committing himself entirely to the cause [מצודת דוד, ביאור שטיינזלץ]. He vows to take action and fulfill the divine promise that David will ultimately rule over the entire nation of Israel [מצודת דוד].

This vow raises a question regarding when exactly God made such a promise to David, as no explicit oath is recorded earlier in the narrative. One approach explains that any statement made by God is inherently considered an absolute oath. However, another perspective suggests that the certainty of this promise comes from repetition. Because God informed Saul on two separate occasions—once at Gilgal and again during the war with Amalek—that the kingdom would be torn from him and given to someone better, this double declaration carries the full weight and binding force of an oath [רד״ק].

Committing to this reality, Abner promises to actively assist David in taking the throne [מצודת דוד, ביאור שטיינזלץ]. Beyond merely offering practical military and political help, his declaration reveals a profound dual realization. He fully understands that establishing David as king is a reality orchestrated entirely by God. At the same time, he recognizes that he has been specifically chosen to serve as the divine messenger and instrument, tasked with bringing God's will into reality and completing the transition of power [מלבי״ם].