In a moment of crisis, a hunted leader is urged to look past his current struggles and focus on his bright destiny. Abigail intervenes to stop David from committing an act of violence, using his future kingship as the ultimate reason to show restraint and avoid shedding blood. She reminds him of the divine promise that his future is secure, specifically God's guarantee to appoint him as the ruler and king over Israel [מצודת דוד, ביאור שטיינזלץ]. The time she refers to is the actual period when David will sit on the throne [רש״י]. Her words also reveal that David's anointing is no longer a hidden matter, as the news of his destiny to rule has already reached the public [ביאור שטיינזלץ].
By bringing up his future kingship, Abigail skillfully removes the legal justification David relies on for killing Nabal. David believes that because he was already anointed, Nabal's disrespect makes him a rebel against the crown, a crime punishable by death. Abigail counters this by explaining that while God will certainly keep His word, this reality belongs to the future. Right now, David's kingdom is not yet established and his authority is not universally recognized. Therefore, Nabal cannot be legally condemned as a rebel [אלשיך].
Furthermore, since David's rise to power is an absolute certainty, taking justice into his own hands now would create a severe obstacle. Such an action would give King Saul a valid legal excuse to continue hunting him, claiming that David is shedding innocent blood before he even reaches the throne [מלבי״ם]. Beyond the political danger, Abigail warns David of the moral consequences. She poses a sharp question: if he kills a wealthy man now simply for refusing to give him food, how will he be able to sit as a royal judge in the future and condemn a poor person who harms a rich man for denying him charity? [מלבי״ם, אלשיך]. She emphasizes that the foundation of his eternal royal house depends on keeping his hands clean, ensuring no moral flaw stains his future rule [אלשיך].