“If the Son of God had wanted merely to appear, He would certainly have assumed any kind of body, even one better than ours. Instead, it was our own kind of body that He took, and not just in any way. He took it from a pure unstained Virgin, who had not known man. This body was pure and not corrupted by union with man. For since He is indeed the All-powerful and the Craftsman of all things. He made for Himself a temple within the Virgin; that is to say, a body.”Athanasius,On the Incarnation of the Word 8; PG 25, 109; ed.Thomson (Oxford Claredon Press, 1971), p.152
Christians believe that our nature is corrupted by sin. Jesus Christ took our human nature – body, spirit and soul – that was not corrupted by sin. For this reason, he took His body from a Virgin. Because his body was not corrupted by sin, He was the perfect Man. And for he was the perfect man, we can look up to Him and He can help us through this life. God is with us.
Gambero, L., 1999. Mary and the Fathers of the Church 1st ed. Translated by Buffer, T., San Francisco: Ignatius Press. p.101-102