Albert Barnes Commentary 1 Samuel 25:37

"And it came to pass in the morning, when the wine was gone out of Nabal, that his wife told him these things, and his heart died within him, and he became as a stone." — 1 Samuel 25:37 (ASV)

He became as a stone - Probably his violent anger at hearing it brought on a stroke, to which he was predisposed by the drunken revelry of the night before. After lying senseless for ten days, he died.