I Samuel 24-25

"Who is David? And who is the son of Jesse?" (25:10). With these words, Nabal revealed his heart. David was known already as a man of honor and influence, and Nabal's shepherds testified that David's men had protected them in the fields (v16). But Nabal disregarded all this and refused to give anything to David's men, dismissing them arrogantly. Abigail recognized that David was "fighting the battles of the Lord," (v28) and she treated him accordingly.

Part of "sound judgment" (Rom 12:3) is simply being able to recognize good and evil, in our own times, and respond appropriately.