'Foolish' in the Bible

Then Jehu came out to the officers of his master, and they said to him, "Peace? Why did this madman come to you?" And he said to them, "You know the man and his foolish talk."

And they went against his rules, and the agreement which he made with their fathers, and his laws which he gave them; they gave themselves up to things without sense or value, and became foolish like the nations round them, of whom the Lord had said, Do not as they do.