The Ship Looking for God

Book 2 of The Ship trilogy:

As battle engulfs Star City, Otto Boteman hustles aboard the ship moments before it launches. Now a useless stowaway (or dead weight, depending on the view), Otto must constantly prove his worth or get shown the airlock door. But a stunning encounter at the Pearly Gates changes the entire purpose of the ship, and Otto, along with the rest of the crew, must band together to survive a universe far more terrifying than any of them imagined.