Viejo and the Ranger by Cliff Hudgins
Jason Bernard Ramsey II is a man of faith...but he becomes Jack Short, a man who kills whoever gets in his way. He discovers two skills he did not know he had...a fast draw and the ability to kill without remorse. He's at odds with his faith and the law. If you break the law in Texas, you must answer to the Texas Rangers. This duty falls upon Lee Brannon. In a strange twist of fate, Viejo joins with the ranger in the pursuit of other outlaws, and discovers there is no real code of ethics among thieves and no misdeeds go unpunished.