The one who spoke from the burning bush to Moses was, we believe, the preincarnate Christ. So when Moses asked who was speaking to him and the reply was “I Am That I Am” it means about the same as when Jesus calls himself the “Alpha and Omega”. There is a Chrismon that depicts the burning bush.
Rev. Mark Chepulis on Cavalier ND wrote a wonderful sermon for the 4th Sunday in Advent. It is the visit of Mary to Elizabeth. Here is a part of the sermon.
For the Lord visits His people. He visits His people to save them. You it see throughout the Scriptures that man doesn’t go to God, but God visits them. He visits Adam and Eve in the garden, He visits Moses in the burning bush and the Tent of Meeting, He visits Joshua as the Commander of the Lord’s Army. Man doesn’t need to build a tower into the heavens because the Lord visits and comes down to His people.
But in today’s text, it’s different. Today, He doesn’t visit His people as a burning bush, a pillar of fire, as the Angel of the Lord, but He comes to us as one of us; the Lord comes wrapped in flesh. Can you wrap your heads around this: that the God who created the heavens and the earth, the God who spoke into being all that exists, enters into His creation and is, Himself, existing in time and space, in human flesh and blood in the womb of Mary? We confess often in the Creed that Jesus was “for us men and for our salvation came down from heaven and was incarnate by the Holy Spirit of the virgin Mary and was made man,” but can we even begin to understand that God is developing in the womb of a virgin? Can we even begin to wonder at the God of Abraham, Isaac, and Jacob has, in Mary, an earthly mother? The Lord visits His people to save them, He visits for us and for our salvation; to enter His creation via the womb of Mary, to live, to suffer, and to die on a cross.
The Lord’s first stop, the first of our Lord’s visitation as man, recorded in Scripture, is to Elizabeth and John, the baby growing in her aged womb. Two pregnant women who shouldn’t be pregnant. The womb of the senior citizen, Elizabeth, has been opened and is bearing the heralder of the Lamb of God. The womb of the young virgin, Mary, who had never known a man has become fruitful by the power of the Holy Spirit. Jesus and His Prophet, who is to prepare His way, meet for the first time.
And how do Elizabeth and John react with the Lord and His mother’s visitation? Joy. Sheer joy. “And when Elizabeth heard the greeting of Mary, the baby leaped in her womb. And Elizabeth was filled with the Holy Spirit and she exclaimed with a loud cry, ‘Blessed are you among women, and blessed is the fruit of your womb!”