Is it right to call a believer rational even if she cannot prove articulately or give good arguments for her belief in God? Let's just say I ask a believer "Why do you believe in God?" and she simply answered, "Because I've experienced God's grace in my life," and she needs no arguments or other evidences for her belief, is her position justifiable? I personally thinks it is but if that is the case, then what would make belief in God irrational, if simply certain personal experiences can justify such belief?