The line separating holiness from ungodliness is a narrow one and walking it, it is as easy to fall to one side as to the other. In fact, depending on the circumstance, it is often easier to fall into ungodliness.
I see a bit of Saul in David in chapter 25. Saul vowed no one would eat anything until he had avenged himself on his enemies (1 Samuel 14). In a fit of rage, he almost killed his son Jonathan and later David. Saul was relentless in his vengance.
David too, having provided protection for Nabal and his herdsmen, is furious when the bill for his protective services is presented. David vows to kill every male in Nabal’s household.
And because the line between holiness and ungodliness is so narrow, we all need advisors along the way to keep us in the way of God. Abigail was just such an advisor and to his credit, macho David listened to her, considering her wisdom a corrective from God.
True wisdom is not just knowing wisdom when you hear it. True wisdom requires following the wisdom you hear no matter what it costs.