Simple: a Family Tree of Religions
You start with ancient Greek, Egyptian and Zoroastrianism stuff, show the (basically) separate beginings of the Bhagavada Gita, Upanishads, all the eastern stuff. Other early religions in other places, yes include those.
I'm talking about an illustration of the EVOLUTION of religion. A picture is worth 1,000 words, and I think such a thing would in general reduce the chances of thermonuclear eschatology.