The nation’s largest Presbyterian denomination, the Presbyterian Church USA, gave its formal approval this week to gay marriage. The 1.8 million-member denomination voted to change its constitution’s definition of marriage from being “between a man and a woman” to “between two people, traditionally a man and a woman.” Last year the church’s general assembly approved the change, which was ratified this week after receiving the majority vote from local districts. The denomination’s increasing openness toward gays in recent years has divided churches and caused many conservatives to leave. Other denominations that officially recognize gay marriage include the United Church of Christ and the Unitarians. The Evangelical Lutheran Church in America does allow clergy to perform gay weddings according to their conscience.