Mary
Luke 1:41-48
Blessed art thou among women, and blessed is the fruit of thy womb... And whence is this to me, that the mother of my Lord should come to me?... For behold from henceforth all generations shall call me blessed.
Context of the passage
At the Visitation, Elizabeth, filled with the Holy Spirit, greets Mary, and Mary responds with the Magnificat.
Catholic reading
Elizabeth's Spirit-inspired title 'Mother of my Lord' affirms Mary's divine motherhood (Theotokos), and Mary's own prophecy that 'all generations shall call me blessed' is fulfilled in the Church's perpetual veneration of her, not idolatrous worship.
Common objection
Calling Mary blessed does not justify Catholic devotions like the Rosary or titles such as 'Mother of God.'
Response
Since Mary's son is truly God (John 1:1,14), calling her 'Mother of my Lord' is equivalent to 'Mother of God,' a title the Council of Ephesus (431) defended precisely to safeguard Christ's full divinity, not to exalt Mary independently of Christ.