From Ohio History Central
During the early 1950s, the Ohio legislature sponsored a contest for selecting a state motto. "With God All Things Are Possible" became Ohio's state motto on October 1, 1959. James Mastronardo, a twelve-year-old boy recommended this quotation from the Bible.
In 1997, the American Civil Liberties Union filed a suit against Ohio and its state motto, claiming that this phrase from the Bible violated the First Amendment to the United States Constitution, which guarantees religious freedom and a separation of church and state. Various federal courts sided with Ohio, allowing the state to retain the motto. Judges ruled that Ohio's motto does not endorse a specific God and, thus, was not a violation of the First Amendment. Ohio is one of five states with the word "God" in their mottos.