a)Because unbeleif is the worst sin anyone could commit.
b)Unbelief is a reflection of a bad heart condition.
c)Clearly unbeleif is a willful rejection of God's creatorship, because the evidence abounds as to His existence.
d)The fool has said in his heart,"there is no Jehovah." and the God of Love hates fools.
e)It is all just a clever mind control indoctrinating idea that has kept billions in slavery, making them fearful of ever loosing faith, and thus making it possible for Christianity to survive longer than other myths.