The early Christian Ecumenical Councils played a key role in developing the church's understanding of Jesus. The Councils defined Christianity and clarified important doctrines such as the dual nature of Christ as both human and divine. The Councils condemned heresies like Arianism and developed creedal statements of faith. Over several centuries, the Councils further refined Christian theology on issues such as the relationship between Christ's human and divine wills. The Councils helped establish orthodox Christian doctrine and shape the church.