How did Christ, being the Son of God, become man?

Christ the Son of God became man, by taking to himself a true body, and a reasonable soul, being conceived by the power of the Holy Ghost in the womb of the virgin Mary, of her substance, and born of her, yet without sin.

Proofs

• Christ the Son of God became man, by taking to himself a true body, and a reasonable soul, (John 1:14; Matthew 26:38)
• being conceived by the power of the Holy Ghost in the womb of the virgin Mary, of her substance, and born of her, (Luke 1:27, 31, 35, 42; Galatians 4:4)
• yet without sin. (Hebrews 4:15; 7:26)