If a prophet came and performed literal miracles, would you believe in god then?

Current Events

Even if the miracles are legit and the prophet is Christian, why would that mean there is a Christian god?

  • Can the prophet be lying?
  • Can the miracles be from another source (technology that is alien or yet undiscovered)?
  • Can it be from another god? Or better yet the 'devil'?
  • Why must the existence of miracles portend some higher power?