Without the statements, I can't specifically answer your question. But, I can present the largest piece of evidence we have for the Big Bang Theory.
Over the course of many many years, we have noticed something. Everything is expanding outwards.
We can observe this, and realise that since things are expanding outwards, or, away from something, everything once came from a fixed point.
Life and the universe started from one point, and every single thing in our cosmos is still expanding away from it. =)
