Mary has the title of Birth-giver of God or Theotokos. She is honored more than any of the other saints, even higher than the angels. In Scripture we see the angel Gabriel venerate her and also the Mother of Saint John the Baptist, Elizabeth. (Lk 1:28-29; 40-43) Luke records, “for behold, from henceforth all generations shall call me blessed. for He that is mighty hath done to me great things…” (Lk 1:48-49). In our services we cry out boldly, “Most Holy Theotokos, save us!”
Elder Cleopa says this about the high place we give to Mary who we say is most holy.
The veneration that we render unto her is called honorific and reverential, as she is the Mother of the Lord, having not only a spiritual relationship with Him, as happens with other saints, but also a physical union with Him. For this reason we chant in the Church’s hymn to her: “It is truly meet to call thee blest, the Theotokos, the ever-blessed and all-immaaculate, and Mother of our God. More honorable than the cherubim, and beyond compare than the Seraphim, thee who without corruption gave birth to the God the Word, the very Theotokos we magnify thee.” She is higher than the saints and the angels, and therefore from angels and saints she receives veneration. Thus it was that the Archangel Gabriel venerated her in the Annunciation. And in the same manner did Elizabeth, the Mother of Saint John the Baptist, also venerate her. The holy Virgin herself prophesied in the Holy Spirit that all generations would honor her: “for behold, from henceforth all generations shall call me blessed, For He that is might has done to me greg things…” (Lk 1:48-49) Hence, the honor rendered to her is according to the will of God.
How is we can say in our prayers, “Most Holy Theotokos save us”, or, “We have no other hope beside thee”?
Regarding the prayer, “We have no other hope besides thee”, Elder Cleopa tells us the meaning is as follows:
With this we do not deny the uniqueness of Christ as mediator of our salvation, yet neither are we indifferent to the rendering of any sort of help related to our personal salvation. The meaning of this expression is as follows: “You can give us the most help for our personal salvation” or “another superior helper we cannot find, nor in one of the saints.” Or, “We have none other who is able to help us as much as you, O Mother of the Savior.”
Regarding the exclamation, “Most Holy Theotokos save us” the Elder gives the following interpretation:
This expression means: “Entreat your Son to save us,” or “Redeem us.” In the Greek language… the word save means to redeem from evil, temptations, distress and necessity. Consequently, it means: “Help us by your prayer to be redeemed from evil, from the works of the devil, from our passions.” Therefore, by “save us” we don’t mean “forgive us of our sins,” but “entreat your Son for our salvation.” … All veneration shown to the Mother of God is a constituent part of the veneration shown her Son, Who chose her and blessed her to be His Mother.
In Scripture we are told the following:
God foretold us that after the fall of Adam and Eve the Mother of the Lord would be a woman-virgin who with her Son would slay the head of the dragon. (Gen 3:15)
Isaiah prophesied that this virgin would give birth to Emmanuel-God. (Is 7:13)
Archangel Gabriel showed her veneration she calling her “full of grace” and “blessed art thou among women.” (Lk 1:28)
Elizabeth, the mother of Saint John the Baptist, venerated her calling out, “blessed art thou among women” and Mother of my Lord.” (Lk 1:40-43)
Jesus was obedient to his mother (Lk 2:51)
Jesus’ first miracle happened in Cana of Galilee at her request. (Jn 2:3-10)
Christ cared for her when he was Suffering on the Cross when he entrusted her care to the most beloved of his disciples John. (Jn 19:26-27)
She prophesied in the Holy Spirit that all generations would call her blessed and venerate her on account of of the glory God granted her on the account of her humility.
We also know that she will be standing at the right hand of the throne of Her Son at the Last Judgment.
Elder Cleopa further says,
How can we not honor the Mother of God when Scripture itself shows us that even the archangel Gabriel esteemed her worthy of honorable veneration? How can we not venerate the Theotokos who is the Church of the King of glory and is glorified above the heavens, since she bore in her womb God, whose glory can be contained neither in heaven or in earth? For this reason we venerate the Mother of God who, according to the testimonies of Scripture and of the Evangelist, is “full of grace.” Likewise, for this reason the Theotokos is considered a woman of great virtue, for she had grace from God and was blessed among women.
Reference: The Truth of Our Faith, 80-92.