Let's say for reasons of explaining myself that I could travel through time to the past. I brought with a me a lighter, flashlight, cassette
recorder and medicine to heal. You could be sure that people at that when would label me a God with these ordinary items listed. I could make fire
with my bare hands. I can make light when it's dark. I could trap voices in a box. I can heal people. I would be written and would be so for
thousands of years. And you would believe. Would you not? Is there a secret that could be as real as this?
I remember reading a short story years ago in which someone had the same idea.
A time traveller went to Ancient Rome with just the same things you mentioned.
The lighter ran out of lighter fuel, the flashlight ran out of batteries, as did the cassette recorder. Our erstwhile time traveller ended up as a
slave in one of Nero's galleys.
Don't forget a gun and lots of ammo. People will question your power and some will try to kill you. People may accuse you of being a witch or even
the devil, you need to defend yourself somehow.
Enter, Evil Dead 3 - Armies of Darkness - transported back to medieval times, with a car, a chainsaw, a shotgun and a trunk full of modern reference
books...