We believe that by this conception the person of the Son of God is inseparably united and joined with the human nature,1 so that there are not two sons of God, nor two persons, but two natures united in one single person. Each nature retains its own distinct properties: His divine nature has always remained uncreated, without beginning of days or end of life (Heb 7:3), filling heaven and earth.2 His human nature has not lost its properties; it has beginning of days and remains created. It is finite and retains all the properties of a true body.3 Even though, by His resurrection, He has given immortality to His human nature, He has not changed its reality,4 since our salvation and resurrection also depend on the reality of His body.5

However, these two natures are so closely united in one person that they were not even separated by His death. Therefore, what He, when dying, committed into the hands of His Father was a real human spirit that departed from His body.6 Meanwhile His divinity always remained united with His human nature, even when He was lying in the grave.7 And the divine nature always remained in Him just as it was in Him when He was a little child, even though it did not manifest itself as such for a little while. For this reason we profess Him to be true God and true man: true God in order to conquer death by His power; and true man that He might die for us according to the infirmity of His flesh.

1Jn 1:14, 10:30; Rom 9:5; Php 2:6-7
2Mt 28:20
3 1 Tim 2:5
4Mt 26:11; Lk 24:39; Jn 20:25; Acts 1:3, 11, 3:21; Heb 2:9
5 1 Cor 15:21; Php 3:21
6Mt 27:50
7Rom 1:4