The motion only proves an outward trajectory from a fairly common place of origin for much of the observable mass that surrounds us. It says nothing to whether or not this was the first such event, nor can we really know for certain what started the mass on that trajectory. Nor can we, personally, even know how much of the observable mass truly adheres to some "trajectory" we are only ever informed of, and how much other mass has never even been examined or can't be due to current technological limitations. Which is why it is all only a guess. A guess at something that happened BILLIONS of years ago. It is actually fairly dumb to pretend you have any idea what happened.
How is this a serous question? Substance? All around us. We get to interact with it, we are made of it, it is literally anything and everything we're able to grasp using our bodily senses. Spirit? Does it even exist? Ever interacted with it? Maybe you would say you have, but I never have. What is it made of, if not "substance?" If it is not substance... then I would argue that it is insubstantial... and, indeed, unsubstantiated. Nor can it be substantiated. You can't prove to me it is there. Substance however... is a "duh" sort of idea. Here I am, typing on a keyboard made of substance. I wouldn't be able to eat lunch this afternoon were it not for the substance of my mouth and digestive tract, and also the various substances that will go into the sandwich I put together, or the soup I heat up. Spirit, however, doesn't make such marks on our daily lives - and has never made a mark in my life whatsoever (which, I might add, is the same story for A LOT of people). A more serious question is "Who gives a crap about 'spirit'?"
Also unsubstantiated, and incapable of being substantiated.