'Foolish' in the Bible

who said by the Holy Spirit through your servant David our forefather, 'Why do the nations rage, and the peoples plot foolish things?

Also some of the Epicurean and Stoic philosophers were conversing with him, and some were asking, "What does this foolish babbler want to say?" Others said, "He seems to be a proclaimer of foreign gods." (They said this because he was proclaiming the good news about Jesus and the resurrection.)