What "spark"? There was no "spark". Just a continuous evolution until the collections of "chemicals and elements" acquired the properties we require them to have in order for us to call them "alive".We might know what early life looked like and what it was made of, but we still don't know what that spark was that turned chemicals and elements into a living thing.
Until we have conclusive evidence that what people experience is real and not imaginary we must assume their experiences are imaginary.I disagree on the observations comment. People have been having religious and supernatural experiences for thousands of years. It might not be something that can be replicated or explained but it's still something they experienced. To write them all off as delusions or tricks of the mind would be foolish.