Before the beginning, when they didn't even want to know about heaven, and long before there was a manmade event that sent so many souls to heaven that people had to finally talk about it, the weapon of choice was poop. Humans learned about this weapon from their closest cousins, the chimpanzees. Chimps would throw poop like their life depended on it, as it often did: leopards. You didn't want to mess with a leopard then and you don't want to now. Chimps knew that, and they discovered early on that poop would knock a leopard on its back and then chase it off quicker than they could say "eekekeeeeeekeee oo oo oo oo". It was a grand time to be alive.
As the milleniums flew by like dragonflies at cruising speed, neanderthals and two or three other human gene pools would gather around the campfires and swap stories. Throwing poop was one of the main topics of discussion, and for good reason. Leopards.
This went on for so long, and the sun and moon went around so many times, that nobody bothered to keep count anymore. Stone age tools evolved everywhere as rocks were shaped into knives and arrowheads, grain mashers and hammers, drills and ceremonial artwork. The best crafted rocks took opening night crowds on some swell neurological journeys, and good stone workmanship found so many uses that people thought rocks were the most important thing in the world. The ancient neanderthal axiom "Sticks and stones..." was the motto of the time. Although stone warfare was bloody and stone hatchets ruled, still not that many people died - at least not enough to bring up the topic of heaven. Because just the threat of being cut deep by a sharp rock was enough to keep the guys separated into their own plots of jungle, prairie, or grassy knoll. There were plenty wide-open nature spaces around then, along with enough caves and granite to keep everyone happy and swapping stories.
Stones were all that was new for a long time. For lots of moons and lots of suns. And aside from rudimentary standoffs and jumping up and down, people got along with each other as long as they kept their distance. Then agriculture reared its ugly head.
Agriculture tied homosapiens and neanderthals to one land area and created a lot of tension, and now everyone worried about how they were going to protect it. Women were there too.
Next, plumbing just had to make an entrance, or else. Even so, for lots of sunmoons liquidy chaos and insect borne disease played skin-the-tail-on-the-monkey with the human race, and heaven was a one-stop-away black-tie affair for many of our ancestors. But they did get plumbing, and with that it seems that all of the ingredients were in place for something so audacious that it would launch the balloon transporting souls straight out to heaven and beyond.
Nobody knows exactly how it happened, the exact timeline, or the name of the mad-stone age scientist who likely ate some mushrooms and thought it up, but a new discovery looks to be the deep fertilized historical roots of going to heaven.
The Stairway To Heaven turns out to be a ride on a shit cannon. This amazing fact was dug up recently by a team of archeologists in the remote sands of the Sahara desert (which, by the way, blooms every few thousand years because of the vast reserve of water underneath it - where the reserve pops-up above sand, that's what nomads and camels call an oasis!). The stone-age tablet instruction sheet which came with the cannon describes it as a leopard fighting device powered by some kind of alien engine. And as the Stairway To Heaven.
The aptly named Stairway consists of a toilet atop what seems to be a crude stone cannon, and was the first major advance on the efficiency of poop throwing monkeys. First used by sapiens and neos to sling poop at leopards, and powered by some kind of Chinese stong-age explosive, at some point a bolt of genius (those pesky mushrooms again) hit an ambitious sapien, and he aimed the shit cannon at a group of his fellows. This friendly-fire instantly revolutionized what arms dealers call "projectile weapons", and gave rise to the use and popularity of sticking-other-things-in-there and throwing them at people.
War would never be safe again.