suppose we meet one claiming to be a prophet, how can we check the validity of this claim? there are some answers mentioned in theology and they could be categorized like this : 1 - another prophet who we already know introduce the one. 2 - by gathering different evidences like the biography and the characteristic etc. 3 - Miracle ! it is obvious, as I see, the best way is the third and the first method depends on the 2 and 3 at the end. OK! the question is "How to do this for one who has passed away?" if we can't see their miracle, how then we want to check their claims?