First, although the Bible documents that Mary became the mother of Jesus and clearly teaches that Jesus is God, it never states, or even implies, that Mary was (or is) the “Mother of God.” For a theological syllogism to explain correctly the relationship between Mary and God, it must be based on biblical truth. We can propose correctly that (1) Jesus is God (Hebrews 1:8); (2) God became flesh (John 1:1,14); (3) therefore, Mary is the mother of Jesus according to the flesh (Romans 9:5), i.e., Jesus’ physical body.
Second, we should keep in mind that Deity is not constituted by a literal family—with fathers, mothers, sons, and daughters—like some of the gods of Greek and Roman mythology. Although we refer to the first and second Persons of the Godhead as the Father and the Son, these titles do not denote a literal familial bond, but emphasize Their united and divine nature. To refer to Mary as the “Mother of God” is to misunderstand the nature of Deity and misapply Scripture.
Third, consider the consequences which develop from such an inappropriate use of the syllogism aforementioned. Since the Bible records that Mary conceived by the Holy Spirit (Matthew 1:18), Catholics conclude that it is correct to refer to Mary as “the daughter of God the Father, Mother of Jesus Christ, and true spouse of the Holy Spirit” (Peffley, n.d., p. 3). If the Holy Spirit is Mary’s “husband” (and, therefore, Jesus’ “father”), and Jesus is God, would not the Holy Spirit be the “father” of God? This is not only a completely erroneous application of Scripture, but also blasphemous theology. Now let us consider some additional evidence from the Bible that further explains Mary’s relationship to God.
God does not have a physical mother
Speaking to the Son, the Father declared, “Your throne, O God, is forever and ever” (Hebrews 1:8, emp. added). In God’s revelation to the apostle John, the resurrected Christ said, “I am the Alpha and the Omega, the Beginning and the End,...who is and who was and who is to come” (Revelation 1:8, emp. added). The Son did not have a beginning; He is the Beginning. “He was in the beginning with God” (John 1:1-2). Paul pointed out, “He is before all things, and in Him all things consist” (Colossians 1:17, emp. added).
The Son’s existence did not begin with His conception in Mary’s womb. He was alive in eternity (cf. Micah 5:2), and, at the right time in history, He became flesh (John 1:1,14). Paul put it this way: “But when the fullness of time had come, God sent forth His Son, born of a woman, born under the law” (Galatians 4:4). On the other hand, Mary came into a time-bound world long after the creation of the Universe. She, like all human beings, was not eternal. She was not divine, not “from everlasting to everlasting” (Micah 5:2). She could not have provided an eternal nature to her Son. He is Deity. He is the “eternally blessed God” (Romans 9:5).
Consider how Jesus explained His divine nature. When addressing the Pharisees, He asked them: “‘What do you think about the Christ? Whose Son is He?’ They said to Him, ‘The son of David.’ He said to them, ‘How then does David in the Spirit call Him ‘Lord’.... If David then calls Him ‘Lord,’ how is He his Son?’” (Matthew 22:42-45, emp. added). The Pharisees failed to answer the question correctly because they were thinking about the physical nature of the Messiah. While Christ was a physical descendant of David (cf. Luke 1:32; Matthew 1:1), according to His divine nature He did not have a physical father, since He Himself is before all (John 8:58). In the same way that David could not be the father of the divine Messiah since he called Him “Lord,” Mary cannot be the “Mother of God” since she calls Him “Lord” in Luke 1:38,46-47. The truth is, as Paul explains, “according to the flesh, Christ came” through the patriarchs, David, and, yes, Mary, but according to His deity, He is the “eternally blessed God” who is over all (Romans 9:5, emp. added).
http://www.apologeticspress.org/apcontent.aspx?category=11&article=2670
Again, the "mother of God" concept by the RCC is another attempt to twist Scripture to fit their false teaching regarding Mary.
You still won’t identify the denomination, sect, or cult you learned this from. I proved only from the Scriptures that Miriam/Mary is the mother of Emmanuel, which the Spirit of God interprets as “God with us” and still you still you deny the clear inspired Scripture means what it says.
Jesus was/is God. full-stop. Mary bore Him and was His mother, hence she was the bearer i.e. the mother of God
If you state therefore, Mary is the mother of Jesus according to the flesh (Romans 9:5), i.e., Jesus’ physical body you are separating out Jesus the 100% man and Jesus the 100% God -- that is wrong. Jesus was fully man and fully God, both natures intertwined. If you say that she bore only His human nature, that means a sense of Adoptionism, as if you would state that Jesus the man was "possessed" by the Holy Spirit at the time of His baptism
if you reject the term “Mother of God” what exactly do you call Mary? The mother of His human nature? Then did she bear only His human nature? What happened to His divine nature?