We must assert that there can be only one Christian family, only one Christian faith, hope and baptism, and only one Christian body, because there is only one God, Father, Son, and Holy Spirit.  You can no more multiply churches than you can multiply Gods.  Is there only one God?  Then he has only one church.... The unity of the church is as indestructible as the unity of God himself.  It is no more possible to split the church than it is possible to split the Godhead.1

John R.W. Stott, The Message of Ephesians.