מלכים א, פרק י״א, פסוק י״ב

The consequence for Solomon's actions is a fractured kingdom, yet the full weight of this judgment is delayed. God chooses to postpone the punishment until the next generation out of consideration for the divine promise previously made to David. Throughout his lifetime, Solomon is allowed to maintain his rule, and the division of the kingdom will not take place while he is alive. This delay is granted entirely due to the merit of his father [ביאור שטיינזלץ].

Beyond David's general merit, the delay is rooted in the specific nature of the original promise God made to him. God granted the kingship to David's direct son unconditionally and absolutely. Because of this absolute guarantee, the rule cannot be stripped from Solomon during his own life. In contrast, the promise that the royal line would continue into future generations was not absolute. It was strictly conditional, requiring David's descendants to faithfully keep God's covenant. Since this condition was broken, the judgment is activated, but it will only take effect in the following generation, tearing the kingdom away from Solomon's son [מלבי״ם, ביאור שטיינזלץ].