“Another great mystery in the way of sanctification, is … our being in Christ, and having Christ Himself in us … I may well call this a mystical union … It is one of the three mystical unions that are the chief mysteries in religion. The other two are, the union of the Trinity of Persons in one Godhead, and the union of the divine and human natures in one person, Jesus Christ, God and man.” (Walter Marshall, The Gospel Mystery of Sanctification, p.21)