I once had a Mormon missionary tell me he was sure of the religious tenets he was speaking about. I started to tell him that I was disappointed he had no faith, but chose not to. It would have done no good.
I happen to know that if you get on Interstate 95 from...
faith - firm belief in something for which there is no proof
certainty - the quality or state of being certain especially on the basis of evidence
faith allows for hope and continuence
certainty is only what is proven