He's already been back. Dostoevsky covered the event in his piece, The Grand Inquisitor. It was during the time of the Inquisition. God, disappointed with the way man was screwing up, sent Christ back to see if he could maybe tidy things a little. But, like the first time around his preaching only managed to rile up the establishment and get him arrested. Torquemada, the Grand Inquisitor, visited Christ in his jail cell and informed him that he had no right to pay us a return visit just to tweak things, that he'd already had his chance, and besides he'd turned over all authority to the Church when he'd wined and dined those twelve guys at that famous supper he threw. Christ had bound himself to the promise that he wouldn't be back until the final curtain had fallen on this farce his old man had set in motion back in the day. So, in all fairness, God had no choice but to honor the deal and leave us to our own devices until...well, coming soon to a local theater, according to you.

Sorry, Shelly.