Why is it that Mary needed to be sinless? Because this made her the fitting mother for the Son of God. And just as she fully cooperated with the grace God gave her, so too can we cooperate with the grace God gives us.
Genesis 3:15 is sometimes referred to as the “protogospel”. That is, the first gospel. “I will put enmity between you and the woman, and between your offspring and hers.” In other words, this is the first promise of a redeemer. And this promise tells us the redeemer will be an offspring of the woman, of Mary, the Mother of God.
Mary the mother of Jesus is never identified by name in the gospel of John. And while today’s gospel comes from the gospel of Luke, the message remains: we give the Mother of God such reverence first and foremost because of her tremendous faith. She trusted God. She believed in God. There were days like today in the gospel where she might have wondered about whether or not she was on the right track. But in all of this, her faith, her example, her life, all these things were ordered to God in a way that helped her to understand and know what was most important. May it be the same for each one of us.