What a great subject and what a great question!
I would like to quote a bible verse. I wanted to point here that it is not abou religion. It is about the wisdom that is in the bible, as well in buddism, kabala, koran or hindu. The same basic truth.
“Whoever prays, believing that he already has it, he will have what he says.”
So, following the ancient wisdom, we need to pray as we alreay have it. Eg. Thank you, I am in perfect health. or I am so incredibly grateful that I am in perfect health.
Knowing that verse, what do you think, should we approach the prayer from inside or outside?