Why is Mary the Mother of Jesus: the Mother of God?
Not merely because she conceived Him.
Not merely because she bore and birthed Him.
Not merely because she nursed and raised Him.
In our Gospel today He looks around at all those seated around Him and, without denouncing His mother, nor those who came with her, and without denigrating the fact that Mary is indeed His mother, Jesus says, “Here are my mother and my brothers. For whoever does the will of God is my brother and sister and mother.”
How so? In John’s Gospel Jesus says, “…I came down from heaven not to do my own will but the will of the one who sent me,” (John 6:38): in other words the Son of God—the child of God—is the one who does the will of the Father. Anyone who does the will of the Father is therefore a child of God: a brother, a sister, of Jesus.
And why is Mary His Mother? Because when the angel revealed to her the will of the Father she replied, “May it be done to me according to your word,” (Luke 1:38) and the word of the angel, being that he was sent by God to deliver His message, was the expression of God’s will. Thus when we embrace the will of God we not only do so as brothers and sisters of Jesus in obedience to the same Father, but if we submit entirely to His will—in the example of a lowly handmaid perhaps—then we become like Mary, His Mother. By surrendering our own will and subordinating it to the will of God, His Son is able to enter into the world through us: the Word of God takes on flesh in our flesh.
Hence the later words of Jesus to the woman who declared His Mother blessed: “Rather, blessed are those who hear the word of God and observe it,” (Luke 11:28).