What?
Neither of those things are "impossible to grasp". The simple fact that we actually have words to describe the concepts means that the ability to grasp them exists. Both "infinity" and "nothingness" are things that are actually relatively easy to conceptualize, even if we can not concretely replicate them in a physical sense (like, just because it's impossible to actually write the infinite number of pi doesn't mean we can't conceptualize it).
I mean, hell, attempting to argue that we can't "imagine" infinity is moronic, considering that there are ENTIRE diciplines of mathematics that deal explicitly with conceptualizing infinite numbers.