What is the meaning of: He was conceived by the Holy Spirit, born of the virgin Mary?
God’s eternal Son, who is and remains true and eternal God, took upon Himself true human nature from the flesh and blood of the virgin Mary, through the work of the Holy Spirit. In this way He is also the true descendant of David, like His brothers and sisters in all things except sin.
What benefit do you receive by Christ's holy conception and birth?
That He is our Mediator, and with His innocence and perfect holiness covers in the sight of God my sins, in which I was conceived and born.