When speaking of epistemic notions, almost all epistemologists agree that things like reason and sense experience can be used in gaining knowledge. But can faith be used in gaining knowledge? I don’t think so.
Faith isn’t an epistemic category because it does not give us any new information about the world. It’s true that someone might say, “I know Christ by faith,” however, this is equivocating the word “know”.
You see, we can use the term “know” in an epistemic sense. But we can also use it in a relational sense. For example, I know Bill in a relational way or I trust Jones.
But suppose you think that we can know things by faith. The problem here is that you can affirm anything and everything by faith. You can say that you know (by faith) that a cat can talk, you could also say that you know by faith that the Raiders are going to win the Superbowl next year. Not only does it seem fishy and very incredible, it actually appears to be meaningless and confused.