James 1:7

So there's this person who lacks wisdom and asks God for it. God is generous and is without reproach in this situation. In asking, this person should ask in faith, expecting that it should be given to him. The thing is that, if he does in fact doubt, he's not going to get anything. It is described here as one who shouldn't even expect to receive anything from God. This is yet another reason why you should ask in faith, though it was perhaps implied by the previous verses.