We all must work out our own salvation with fear and trembling. If you are waiting for someone to "prove" Him to you, then you can easily reject their efforts. However, if you go straight to the source and plead with Him to reveal Himself to you (with a humble and contrite heart...you can't fake this. He will know), He always shows up!

Once He has revealed Himself (different ways to different people), then there is no way to deny that He is real, He is the one True Creator and He loves you enough to provide His Son as your substitute. You don't need a Bible in front of you for Him to reveal all of this to you. You just have to ask!