"The Son of God, the second Person in the Trinity, being very and eternal God, of one substance, and equal with the Father, did, when the fullness of time was come, take upon him man's nature, ...
So that two whole, perfect, and distinct natures, the Godhead and the manhood, were inseparately joined together in one person, without conversion, composition or confusion. Which person is very God and very man, yet one Christ, the only Mediator between God and man."
-- Westminster Confession of Faith, Chapter VIII, Of Christ the Mediator