שמואל ב, פרק ז׳, פסוק ט״ו

God establishes an eternal covenant with the Davidic royal dynasty, ensuring its permanent place in history. This guarantee of everlasting favor stands in sharp contrast to the fate of King Saul. God promises that the covenant with David's descendants will remain forever [ביאור שטיינזלץ]. God will never reject David's line or withdraw His kindness from them [מצודת דוד].

Commentators explore the deep contrast between David and Saul, explaining why divine kindness was taken from Saul but guaranteed forever to David's family. One perspective notes that Saul lost his royal standing as a result of his sin. His removal was necessary to clear the path for David to step into the role and inherit the kingdom in his place [מצודת דוד].

A different approach focuses on the concept of suitability for leadership. According to this view, the unique promise given to the House of David ensures that their royal status will never be revoked, even if someone else arises in the future who is more worthy of ruling. This is in complete contrast to what happened to Saul, whose kingship was taken away for that exact reason. Saul lost the throne simply because David was found to be a more fitting and worthy king than him [מלבי״ם].