Complex sentence: On Easter Sunday, 2006, the church's rector, Father Steven Clark, left the Episcopal Church and took roughly half of the congregation with him to organize St. Gregory's Anglican Church, a parish of the Anglican Church in America.
Split into simpler sentences: On Easter Sunday, 2006, the church's rector, Father Steven Clark, left the Episcopal Church. He took roughly half of the congregation with him as he organized St. Gregory's Anglican Church, which is a parish of the Anglican Church in America.