He began writing and drawing for Archie Comics, infusing some of the stories with his Christian beliefs. At one point he was directed to cut back. "I knew God was in control, so I respected my publisher's position and naturally complied". He later received a call from publisher Fleming H. Revell, for whom he then freelanced a comic-book adaptation of David Wilkerson's "The Cross and the Switchblade" in 1972, quickly followed by adaptations of "God's Smuggler" by the pseudonymous Brother Andrew and "The Hiding Place" by Corrie ten Boom. Inspired, Hartley helped launch the Spire Christian Comics line, and pitched Archie president John L. Goldwater to let him license the Archie guys 'n' gals. The Jewish Goldwater, himself religious, agreed, and Spire went on to release 59 comics – at least 19 of them Archie titles, along with six Bible stories, 12 biography adaptations, four other book or movie adaptations (including "Hansi: The Girl Who Loved the Swastika"), and nine children's comics.