if you don't believe in any god and no god exists, you gain
nothing
if you don't believe in any god and a god exists, you go to
hell
if you believe in a god and no god exists, you gain nothing
if you believe in a god and that god exists, you go to heaven
if you believe in a god but another god exists, you go to
hell
if you believe in all gods and no god exists, you gain
nothing
if you believe in all gods and one of them exists, you go to
heaven
so it pays to believe in all the gods 