The episcopate is the collective boy of all bishops of a church. In the Roman Catholic, Anglican, Eastern Orthodox, Eastern Rite Catholic, Oriental Orthodox, Old-Catholic, and Independent Catholic churches as well as in the Assyrian Church of the East, it is held that only a person in Apostolic Succession, a line of succession of bishops dating back to the Apostles, can be a bishop, and only such a person can validly ordain Christian clergy. The succession must be transmitted from each bishop to a successor by the rite of Holy Orders. Bishops in valid Apostolic Succession compose the historical episcopate. Bishops of the Evangelical Lutheran Church in America are also ordained through the laying on of hands of bishops in the apostolic succession.