Bishop of Lincoln, and scientist, Robert Grosseteste wrote about the Big Bang way back in 1225:

Grosseteste had been studying the recently rediscovered works of Aristotle, which explained the motion of the stars by embedding Earth in a series of nine concentric celestial spheres. In De luce, Grosseteste proposed that the concentric universe began with a flash of light, which pushed everything outwards from a tiny point into a big sphere.
New Scientist, 22 March 2014