Satan need not convince us that Heaven doesn’t exist. He need only convince us that Heaven is a place of boring, unearthly existence. If we believe that lie, we’ll be robbed of our joy and anticipation, we’ll set our minds on this life and not the next, and we won’t be motivated to share our faith. Why should we share the “good news” that people can spend eternity in a boring, ghostly place that even we’re not looking forward to?