As humans you see, we are bound by the laws of Physics and science, i.e. what goes up, must come down, and so on. But if God too were bound by such laws, He'd have no more power than the average human. We'd have no reason to worship Him [being that He'd be no different from any of us], we'd have no reason to ask for His help [being that He'd be no more powerful than any of us], and we'd have no reason to trust Him either [being that human beings do not possess the power to be fully good (so we'd never know whether He was on our side or not)].
So then, in order for God to be God, [that is; all good, all powerful, and all knowing] He would need to possess some abilities that humans do NOT have. He'd have to be suprahuman, and therefore supernatural.
Having these supernatural abilities would render God "more than able" to do what we humans render 'impossible'. So then, parting the Red Sea, no big deal; and feeding five thousand people with the contents of some kid's lunchbox, easy as pie.
If God wasn't able to do more than we could do, there'd be no point calling Him God.