Let’s see how, in the Bible, it is clear that Mary is our mother:

As we are members of the Mystical Body of Jesus Christ and Mary is Christ’s mother, she is also the mother of all this body and she is also our mother. (“We are the sons of God in Jesus Christ”, Gal. 4, 4-6).

In Saint John’s Gospel (19, 26-27), we read what Jesus says from the cross:“When Jesus saw his mother and the disciple whom he loved standing by, he said to his mother, “Woman, behold thy son”. Referring to this passage, the Church teaches us to see ourselves personified and represented in the person of Saint John: From the cross, Jesus gives us Mary as our mother. For Protestants, who see in this passage just an event referred exclusively to Saint John, we can still mention another passage of the Bible:

In Apocalypse 12,4-6, we can read:“…And his tail was dragging along the third  part
of the stars and of heaven, and it dashed them to the earth, and the dragon stood before the woman who was about to bring forth, that when she had brought forth he might devour the son. And she brought forth a male child, who is to rule all nations with a rod of iron…”If the son has to rule the nations with an iron rod, it means that He has the supreme authority. He is, therefore, Christ. If the son is Christ, Maria is His mother.

Let’s read on in Apocalypse 12, 17 :“ And the dragon was angered at the woman, and went away to wage war with the rest of her offspring, which keeps the commandments of God, and holds fast the testimony of Jesus”.. We see that the dragon wants to wage war against the rest of her offspring, that means the sons of Mary, the loyal believers, those who keep God’s precepts and hold the testimony of Jesus (all are called to be sons of Mary but only those who are loyal to Christ or repent not having been loyal to Him are properly her sons).Thus, according to this passage, Maria is the mother of all loyal Christians.

 In a general sense, we can also quote the passage of Saint Luke 1, 38, when the blessed Virgin Mary says:“Behold the handmaid of the Lord, be it done to me according to thy Word”. Mary, the only human creature that is absolutely beautiful to the eyes of the Lord, says “yes” to God, as she spoke in the name of all humanity, opening therefore the doors to Redemption through Jesus' Incarnation to all men, enlightening us for the life of grace: She is our mother in the life of God’s grace.