Says who?
Oh, I forgot. It's another infallible pronouncement of dogma from the inerrant and divinely-inspired Pope BibChr.
Pop quiz! Which teaching is true?
1. “Mary is the Mother of God.” - 2,000 years of Christian belief
2. “Mary is not the Mother of God.” - BibChr's personal opinion.
Easy choice. I choose #1.
LOGICAL PROOF
1. Jesus is 100% God.
2. Mary is the mother of 100% of Jesus.
3. THEREFORE Mary is the mother of 100% of God.
QED.