By using our logic and from the experience of things around us we can say that it’s impossible for something to come from nothingness. There is a consensus that the universe has a beginning which scientists call the Big Bang. But that cannot come out of itself, logic dictates that there is something which brought it about (energy/matter does not just compress itself into a singularity). Whatever that thing is or things if there is a chain of initiators/causes, must end with an initiator which is self-sufficient and which has not been caused by something else. Otherwise we go in an infinite regression of asking what caused that cause, and an infinite chain going backwards would mean the present never gets to happen, but we exist, and that is proof that the chain ends somewhere.

That’s what is called the necessary being or the uncaused cause.

Now, by observing the universe we can surmise some characteristics that that cause must possess to bring it about, since it must possess them in at least an equal ammount. The enormous ammount of energy held in the universe shows that the initiator has immense power. The laws of the universe and its intricacies suggest that it must possess knowledge and wisdom etc.