The Christian religion was likely transformed 2,000 years ago when Saul, a hard-line persecutor of followers of Jesus, was literally bowled over during the course of one of his many searches for Christians to punish. The event blinded him for three days, allowing him plenty of time for introspection. And thus, he became Paul - and an irresistible force in the spread of Christianity. He was the convert of all converts; sometimes referred to as the second founder of Christianity, and now revered as Saint Paul.
And what bowled him over so remarkably and so suddenly? What caused him to go blind for three days? In all probability, this:

William Hartmann, co-founder of the Planetary Science Institute in the U.S. has connected Paul’s experience with similar accounts of exploding meteors, such as the well-recorded Chelyabinsk meteor which broke up over Russia in 2013, injuring over 1,500 people. The eyewitness descriptions and physical reactions to meteors or fireballs in the sky seem to parallel what is recorded about Paul.
In the biblical accounts, Paul was blinded for three days due to the intense light from the sky; it was “brighter than the sun, shining round me,” according to the text. This matches the Chelyabinsk meteor, as it was calculated to be shining around three times as bright as the sun. The blazing fireball made shadows move around the ground as it travelled.
Paul and his companions were said to have been knocked to the earth, and this also corresponds to the shockwave generated by the powerful Chelyabinsk meteor as it blasted out windows, knocked people off their feet, shook cars and buildings, and collapsed roofs.
Moreover, photokeratitis, sometimes known as corneal burn or ultraviolet keratitis, is known to occur in people who witness an exploding meteor.

It's painful; in fact, intensely so, and generally occurs after six or so hours following unprotected exposure to intense ultraviolet radiation. It also typically self-resolves within a period of three to four days.
Had Saul not been out searching for Christians to punish - with that goal occupying his heart and his mind - he might never have experienced a tap from the hand of God, and world history would likely be completely different.