"The point is this: while God's work is transforming man's human nature – transforming all into Christ – Mary is the one who cares for the person and everything going on in their mundane day-to-day life. So while God takes care of what we are (human nature), Mary takes care of who we are. If God had not planned it this way, then, of course, it wouldn't be true. Although God's transformation of nature can be called a 'grace', yet grace is God's ordinary operandi, not an answer to prayer, nor is grace for the benefit of any person, but only for man's nature.
"So as marvelous as God's transforming work in human nature, Mary's prerogative is care for the individual person – 'who' one is. Because her particular function in God is seeing to the mundane concerns in people's lives, this is why she has been revealed as 'Mother'. Where God's concern is with man's essential nature, Mary's concern is with the individual person(s)."
The Real Christ, Chapter: Theotokos