The Bible Calls Mary the Mother of God
The God of the Old Testament—YHWH Himself—became a baby in Mary’s womb. Elizabeth was filled with the Holy Spirit, saw Mary, and called her the Mother of God.
In the Old Testament, God reveals His personal name to Moses at the burning bush:
YHWH (יְהוָה) — “I AM WHO I AM”
This four-letter name, known as the Tetragrammaton, is the holiest name in all of Judaism. Out of reverence, the Jews avoided pronouncing it, and instead said Adonai (“Lord”) whenever reading Scripture aloud.
So when Jewish scholars translated the Old Testament into Greek (the Septuagint, or LXX) around the 3rd century B.C., they preserved this tradition. Instead of writing “YHWH,” they used the Greek word:
Κύριος (Kyrios) — “Lord”
But this wasn’t just a generic title. In biblical Greek, kyrios became the stand-in for the divine name YHWH. Over 6,000 times, Kyrios is used in the Septuagint to refer directly to the God of Israel.
This matters because Jesus, the apostles, and the first-century Church primarily used the Septuagint.
So whenever the New Testament quotes the Old Testament and says “the Lord,” it’s often using Kyrios in the same way—to refer to YHWH, the personal God of Abraham, Isaac, and Jacob.
And that brings us to a stunning moment in the first chapter of the Gospel of Luke:
A Meeting Between Two Mothers
After the Annunciation, Mary travels to visit her cousin Elizabeth, who is pregnant with John the Baptist.
When Mary greets her, Elizabeth is suddenly filled with the Holy Spirit—and cries out:
“Who am I, that the mother of my Lord should come to me?” (Luke 1:43)
The word “Lord” in Greek is Κύριος (Kyrios) — the same word used in the Greek Old Testament to translate YHWH — the same word Elizabeth would have heard again and again in synagogue Scripture readings as the name of the one true God.
And now — filled with the Holy Spirit — Elizabeth uses the same name for the unborn child in Mary’s womb.
She doesn’t say:
“the mother of the Messiah”
“the mother of the Christ”
or even “the mother of my Savior” (though all of those are true)
She says:
“the mother of my Kyrios”
And in biblical Greek, Kyrios is the name for YHWH.
So read it again, with that meaning unveiled:
“Who am I, that the mother of YHWH should come to me?”
Some critics have assumed that the title “Mother of God” was invented centuries later, hammered out in theological arguments. But Luke 1:43 shows otherwise.
This is Elizabeth, speaking under the power of the Holy Spirit, declaring that the one growing in Mary’s womb is Kyrios — YHWH in the flesh.
And that makes Mary, literally, the Mother of God.
But How Can God Have a Mother?
A fair question—and one that the early Church Fathers were eager to address.
Christ’s divine nature is eternal. He has no beginning. He is begotten of the Father before all ages.
But Christ’s person — the one Person of the Word — took on human nature in Mary’s womb. He didn’t just borrow a body. He didn’t just appear as a man. He became man. And that person miraculously was in Mary’s womb.
When He was born, it wasn’t just His humanity coming into the world. It was the eternal Son of God — the Second Person of the Trinity — who was born of Mary. Mary did not create God, or cause Him to exist. But after God took on human flesh and entered Mary’s womb, she gave birth to Him. She became His mother.
That’s why we don’t say Mary is the mother of Jesus’ body, or His humanity.
We say she is the Mother of the Person, and that Person is God.
This amazing truth can be seen in a single Greek word: Kyrios.
It’s the word used over 6,000 times to refer to God in the Old Testament. It’s the word the apostles use for Jesus again and again.
And it’s the word Elizabeth — prompted by the Holy Spirit — uses for the child in Mary’s womb.
She was the first to acknowledge the truth that we all now confess:
The baby in Mary’s womb is the Lord Himself. And therefore, Mary is the Mother of God.
It’s just the plain meaning of Scripture — written in Greek, inspired by the Holy Spirit, and hiding in plain sight.