It certainly sounds contradictory, but what I see in the lives of the Hebrew patriarchs is "insecure faith." It is as much as reality as jumbo shrimp, military intelligence or other oxymorons. You might call it a paradox for Abraham is certainly elevated to us as an example of faith in Hebrews 11, as are his son, Isaac, and his grandson, Jacob. And yet they all exhibited the signs of insecurity. In fact, you won't find many in the Bible who show it more than these three.