I am confused about this part of Athanasian Creed
"God, of the Essence of the Father; begotten before the worlds; and Man, of the Essence of his Mother, born in the world."
"not by confusion of Essence; but by unity of Person."
Does this two parts means Christ have two natures?
But, also, this part of creed means Christ have one nature
"For as the reasonable soul and flesh is one man; so God and Man is one Christ"
Human have one nature, so, if the incarnation is like unity of soul and body of human, Christ have one nature also.
Someone can explain this?
Thanks very much!