Mark Twain said this quote

The easy confidence with which I know another man's religion is folly teaches me to suspect that my own is also. I would not interfere with any one's religion, either to strengthen it or to weaken it. I am not able to believe one's religion can affect his hereafter one way or the other, no matter what that religion may be. But it may easily be a great comfort to him in this life--hence it is a valuable possession to him.