Sallam,
I have been wondering for a while why miracles were ever a necessity. Miracles are very convincing, I can easily agree - heck, if someone split the sea or the moon infront of me I'd be the first to believe - but why do that?
It seems like a very last-minute make-shift way to respond to argument:
>Debater: If God had given us free-will then our choices should not have consquences.
>Prophet *after he splits the moon*: God sent me down to guide you.
Not to mention, miracles aren't very lasting...
Wassallam