For the first 1600 years of Christianity, the belief that Mary was a virgin all her life was almost universally held. Even Luther, Calvin, and Zwingli affirmed the perpetual virginity of Mary. It was only latter-day Protestants who began to claim that the people referred to in the gospels as the "brethren," or "brothers and sisters," of Christ (Matt. 13:55; Mark 3:31-34; Luke 8:19-20; John 2:12; 7:1, 5; 7:10; Acts 1:14; 1 Cor. 9:5), were actually children of Mary.
So we read: "His mother and his brothers stood outside, asking to speak to him" (Matt. 12:46); "Is not this the carpenter, the son of Mary and brother of James and Joses and Judas and Simon, and are not his sisters here with us?" (Mark 6:3). Protestants interpret the term "brother" in the strict sense, and therefore claim Mary had other children.
But the Greek word for brother, adelphos, had many different meanings when used in the Bible. It could mean relatives. Lot is called Abraham's brother (Gen. 14:14) when in fact Lot is Abraham's nephew (Gen. 11:26-28). The same holds true for Jacob and his uncle Laban (Gen. 29:15). The sons of Kish and the daughters of his brother Eleazar married, but instead of being called cousins, the sons of Kish are called the "brethren" of Eleazar's daughters (1 Chron. 23:21-22). Often enough, brethren referred to kinsmen (Deut. 23:7, Neh. 5:7, Jer. 34:9). Obviously, King Azariah did not have forty-two blood brothers (2 Kings 10:13-14). Even friends or allies were called "brothers" in the Scriptures (1 Sam. 9:13; 20:32; 2 Sam. 1:26; Amos 1:9). In 1 Corinthians 15:6, it says Jesus appeared to 500 "brothers."
Why do we see this? It is because the language spoken by the Biblical writers (Hebrew and Aramaic) did not have a word for "cousin." People who spoke Aramaic and Hebrew would either refer to cousins by saying "the son of the brother of his father," or, since it was simpler, just used the word "brother." Although the Greek in which the New Testament writers wrote in had a separate word for cousin, anepsios, the writers simply used the word for brothers, adelphos, because they were used to using the term "brothers" to refer to cousins. Protestants argue, and say that since Elizabeth is called Mary's "cousin" (Luke 1:36), the New Testament writers are using the word anepsios to refer to cousin. But the actual Greek word used in this passage is suggenes, and it means "kinswoman." The word "cousin" is a poor translation.
Of course, there are other problems with the Protestant interpretation. When the angel Gabriel appeared to Mary, and told her that she would conceive and bear a son, she responded by saying, "How can this be since I do not know man?" (Luke 1:34). Thus, it is apparent that Mary had taken a vow of perpetual virginity. Obviously, she knew how children were conceived (because she said "I do not know man"). She would only be surprised by being told she would have a son if she had planned on remaining a virgin all her life. If she had planned to have marital relations with Joseph, she would not have asked the question, but would have naturally expected that after she was married, she would become pregnant and bear a son.
At the finding in the Temple (Luke 2:41-51), there is no evidence that Mary had other children. Jesus was called "the son of Mary" (Mark 6:3), not "a son of Mary." In the Greek, this implies that Jesus was the only son of Mary. Wherever the Bible refers to the "brothers" of Jesus, it is never said that they are children of Mary, only that they are brothers of Jesus. And at the Cross, Jesus said to Mary, "behold thy son (John)," and said to John, "behold thy mother." (John 19:26-27). In other words, Jesus gave Mary over to the care of John. If Jesus really did have brothers, he would not have given his mother over to the care of John, but rather over to his brothers. And in the society Jesus lived in, it was frowned upon for a younger son to give advice to an older son, yet we see the "brethren" of Jesus advising Him in regards to where he should go (John 7:3-4). This implies that the "brethren of the Lord" were older, and therefore could not have been his blood brothers, because Jesus was the "first-born" of Mary (Luke 2:7).
However, Protestants take issue with the fact that Jesus was called the "first-born." They say this implies that there was a "second-born," and so, they say, Mary must have had other children. But the term "first-born" was given to the first-born child regardless of whether or not the mother had other children. It was a title given to the children born first, and came along with duties and privileges. This is illustrated by a funerary inscription in Egypt which states that the mother died while she was giving birth to her "first-born."
Protestants also cite Matthew 1:25: "And he (Joseph) did not know her (Mary) until she brought forth her firstborn son." The word "until," they say, implies that after she brought forth her first-born, Mary had relations with Joseph. But in the Bible, "until" simply meant something did not happen until a certain point, without implying that it did happen after that point. For instance, the Bible states that "Michal the daughter of Saul had no children until the day of her death" (2 Sam. 6:23). But that does not mean she had children the day she died. The raven released by Noah is said to have gone "to and fro until the waters were dried up from the earth" (Gen. 8:7). But the raven actually never returned. And Deuteronomy 34:6 reads that Moses was buried and that "until this present day" no one knows where he is buried. Of course, on "this present day," no one knew where he was buried either. (Deut. 34:6). But we know that no one has known since that day either. (See also 1 Macc. 5:54). A better translation would be "He had no relations with her at any time before she gave birth to her firstborn son." A similar citation can be found at Matthew 1:18, which reads: "Now the birth of Jesus Christ took place in this way. When his mother Mary had been betrothed to Joseph, before they came together she was found to be with child of the Holy Spirit." Once again, before does not imply that they had relations afterwards. One could say, "before St. Paul went to England, he was beheaded," and mean that Paul was planning on going to England, but he never did get there because he was martyred before he had the chance.
So who were the "brothers" of Jesus? One of the four "brothers" mentioned is James, whose mother was Mary: "among whom were Mary Magdalene, and Mary the mother of James and Joseph, and the mother of the sons of Zebedee" (Matt. 27:56); "There were also women looking on from afar, among whom were Mary Magdalene, and Mary the mother of James the younger and of Joses, and Salome" (Mark 15:40); "But standing by the cross of Jesus were his mother, and his mother's sister, Mary the wife of Clopas, and Mary Magdalene" (John 19:25). Thus, the mother of James and Joseph was the wife of Cleophas. Yes, James is called the son of Alphaeus in Matthew 10:3, but Alphaeus and Cleophas are one in the same, since the Aramaic for "Alphaeus" can be rendered in Greek as Alphaeus or Clopas. It is also possible that, like Saul, he took a new name.
It was not until the fourth century that a man named Helvidius challenged the widely-held belief in Mary's perpetual virginity. Before (and after) this time, Christians believed, almost without exception, that Mary was a virgin all her life. The Protevangelion of James says that Mary was dedicated to the Temple (such as Anna the prophetess in Luke 2:36-37), and was therefore unable to have a family. It was necessary for her to take a vow of lifetime virginity. However, because of ceremonial laws, it was necessary for Mary to take a guardian, a "spouse," who would honor her vow of virginity. This is demonstrated by the fact that Joseph and Mary were accused of breaking the vow when it was discovered that Mary was pregnant.
The Protoevangelium of James (Protoevangelium of James 4, 7 [A.D. 120]) "And [from the time she was three] Mary was in the temple of the Lord as if she were a dove that dwelt there"; (ibid., 8-9) "And when she was twelve years old there was held a council of priests, saying, 'Behold, Mary has reached the age of twelve years in the temple of the Lord. What then shall we do with her, lest perchance she defile the sanctuary of the Lord?' . . . And behold, an angel of the Lord stood by . . . saying, 'Zechariah! Zechariah! Go out and assemble the widowers of the people and let them bring each his rod, and to whomsoever the Lord shall show a sign, his wife shall she be. . . . And Joseph [was chosen] . . . And the priest said to Joseph, 'You have been chosen by lot to take into your keeping the Virgin of the Lord.'"; (ibid., 15) "And Annas the scribe came to him [Joseph] . . . and saw that Mary was with child. And he ran away to the priest and said to him, 'Joseph, whom you did vouch for, has committed a grievous crime.' And the priest said, 'How so?' And he said, 'He has defiled the virgin whom he received out of the temple of the Lord and has married her by stealth'"; (ibid) "And the priest said, 'Mary, why have you done this? And why have you brought your soul low and forgotten the Lord your God?' . . . And she wept bitterly saying, 'As the Lord my God lives, I am pure before him, and know not man'".
Origen (Commentary on Matthew 2:17 [A.D. 248]) "[According to] The Book [The Protevangelium] of James . . . the brethren of Jesus were sons of Joseph by a former wife, whom he married before Mary. Now those who say so wish to preserve the honor of Mary in virginity to the end, so that body of hers which was appointed to minister to the Word . . . might not know intercourse with a man after that the Holy Spirit came into her and the power from on high overshadowed her. And I think it in harmony with reason that Jesus was the firstfruit among men of the purity which consists in chastity, and Mary was among women. For it were not pious to ascribe to any other than to her the first-fruit of virginity".
Hilary (Commentary on Matthew 1:4 [A.D. 354]) "If they [the "brothers" of Jesus] had been Mary's sons and not those taken from Joseph's former marriage, she would never have been given over in the moment of the Passion to the apostle John as his mother, the Lord saying to each, 'Woman, behold your son,' and to John, 'Behold your mother', as he bequeathed filial love to a disciple as a consolation to the one desolate".
Athanasius (Discourses Against the Arians 2:70 [A.D. 360]) "Let those, therefore, who deny that the Son is by nature from the Father and proper to his essence deny also that he took true human flesh from the ever-virgin Mary".
Epiphanius of Salamis (The Man Well-Anchored 120 [A.D. 374]) "We believe in . . . one Lord Jesus Christ . . . who . . . was born perfectly of the holy ever-virgin Mary by the Holy Spirit."
Jerome (Against Helvidius: The Perpetual Virginity of Mary, 21 [A.D. 383]) "We believe that God was born of a virgin, because we read it. We do not believe that Mary was married after she brought forth her Son, because we do not read it. . . . You [Helvidius] say that Mary did not remain a virgin. As for myself, I claim that Joseph himself was a virgin, through Mary, so that a virgin Son might be born of a virginal wedlock".
Didymus (The Trinity 3:4 [A.D. 386]) "It helps us to understand the terms `first-born' and `only-begotten' when the Evangelist tells that Mary remained a virgin `until she brought forth her first-born son'; for neither did Mary, who is to be honored and praised above all others, marry anyone else, nor did she ever become the Mother of anyone else, but even after childbirth she remained always and forever an immaculate virgin".
Ambrose of Milan (Letters 63:111 [A.D. 388]) "Imitate her [Mary], holy mothers, who in her only dearly beloved Son set forth so great an example of material virtue; for neither have you sweeter children, nor did the Virgin seek the consolation of being able to bear another son".
Pope Siricius I (Letter to Bishop Anysius [A.D. 392]) "You had good reason to be horrified at the thought that another birth might issue from the same virginal womb from which Christ was born according to the flesh. For the Lord Jesus would never have chosen to be born of a virgin if he had ever judged that she would be so incontinent as to contaminate with the seed of human intercourse the birthplace of the Lord's body, that court of the eternal king".
Augustine (Heresies 56 [A.D. 428]) "Heretics called Antidicomarites are those who contradict the perpetual virginity of Mary and affirm that after Christ was born she was joined as one with her husband".
Cyril of Alexandria (Against Those Who Do Not Wish to Confess That the Holy Virgin is the Mother of God 4 [A.D. 430]) "The Word himself, coming into the Blessed Virgin herself, assumed for himself his own temple from the substance of the Virgin and came forth from her a man in all that could be externally discerned, while interiorly he was true God. Therefore he kept his Mother a virgin even after her child-bearing".