How many women were at the cross?

To support their contention that the terms αδελφος and αδελφη (brother/sister) can have a broad semantic force for family members, even during the time of the New Testament, some Catholic apologists and scholars (e.g., Tim Staples; Brant Pitre) appeal to John 19:25:

Near the cross of Jesus stood his mother and his mother's sister (αδελφη), Mary the wife of Clopas, and Mary of Magdala. (New Jerusalem Bible)

According to these apologists, as it is a stretch to claim that Mary (the mother of Jesus) had a biological sister also called “Mary,” the designation αδελφη can mean something much broader than a uterine sibling, and, as a result, the same must hold true for the “brothers” (αδελφοι) of Jesus who are mentioned in the Gospels and elsewhere.

The fatal flaw of this interpretation is that the Catholic assumes a priori that “his mother’s sister” is numerically identical to “Mary the wife of Clopas” [Greek: Μαρία ἡ τοῦ Κλωπᾶ [lit. Mary of Clopas, indicating she could be a near-relative of Clopas, not just a wife]). This is falsified for a number of reasons.

For example, early Christian interpreters understood that “[Christ’s] mother’s sister” and “Mary of Clopas” to be different people. The Peshitta adds a conjunction between these two figures, treating them as separate, not identical, people:

Etheridge, in his 1849 translation of the Peshitta, rendered the verse thusly:

But there stood by the cross of Jeshu his mother, and the sister of his mother, and Mariam, she who was (the wife) of Clopha, and Marian Magdalitha.

In addition, the only way to make sense of all the lists of the women at the cross is to suppose that John speaks of four people and that the mother of James and Joses in Matt 27:55 is not “another Mary,” but the mother of Jesus. Arguing against this latter point, Dr. Brant Pitre, in a recent blog post comment, stated:

If the brothers “James and Joseph” (Matt 13:55) are in fact the children of Jesus’ mother, then why does Matthew refer to “James and Joseph” as the sons of “the other Mary” (ἡ ἄλλη Μαρία) (Matt 27:56)?

For a well-respected and capable scholar, this is a rather weak argument against the author of the blog post (Anthony Le Donne); Pitre is really forced to engage in weak eisegesis instead of meaningful exegesis to prop up belief in a belief he must hold to, it being a dogma of the Roman Church and Pitre being a Catholic, so one must note the bias from the get-go. Furthermore, commenting on Matt 27:55-56, D.A. Carson wrote:

Comparison of the lists of names in Matthew, Mark, and John (19:25) produces these results:

Matthew	Mark	John
Mary Magdalene	Mary Magdalene	Jesus’ Mother
Mary, the mother of James and Joses	Mary the mother of James the younger and Joses	Jesus’ mother’s sister
Mother of Zebedee’s sons	Salome	Mary wife of Clopas
		Mary of Magdala

If we make two assumptions—(1) that John’s second entry is distinguished from his third (i.e., they were not in apposition) and (2) that John’s list of four includes the list of three in Matthew and Mark—then certain things become probable. First, the mother of Zebedee’s sons was called Salome, unless a different woman is here introduced. Second, if Mary, the mother of James and Joseph (or Joses) is Jesus’ mother (cf. 13:55), then Jesus’ mother and Mary Magdalene (or Magdala) appear on all three lists. That would make Salome Jesus’ mother’s sister—his aunt on his mother’s side. Others suppose that Mary the wife of Clopas is the mother of James and Joses, who are not Jesus’ half-brothers. Yet the result still equates Salome and Jesus’ aunt on his mother’s side. Although none of this is certain, it would help explain 20:20. (D.A. Carson, “Matthew” in The Expositor’s Bible Commentary, ed. Frank E. Gaebelein [vol. 8: Grand Rapids, Mich.: Eerdmans, 1984], 583)

In a later commentary on the Gospel of John, Carson wrote on John 19:25 the following:

The primary reason why these identifications [Mary of Clopas being the sister of the mother of Jesus and this Mary of Clopas being the mother of James and Joses] cannot be certain is that Mark tells us, ‘Many other women who had come up with him to Jerusalem were also there’ (Mk. 15:41), and therefore the lists should not necessarily be mapped onto each other. In favour of the traditional interpretation, however, are two details: (1) assuming that John is the believed disciple (cf. vv. 26-27) who stands behind the Fourth Gospel, it is remarkable that he alone of the Evangelists mentions neither his own name nor the name of his brother—which makes it unsurprising that his mother, the sister of Mary the mother of Jesus, is also unnamed; (b) Jesus’ assignation of a connection between his other and the beloved disciple (vv.26-27) becomes somewhat easier on the assumption that John is his cousin on his mother’s side, his mother’s nephew. (D.A. Carson, The Gospel of John [The Pillar New Testament Commentary; Nottingham, England: Apollos, 1990], 616)

For a full discussion of the relevant issues, see the book by Eric D. Svendsen, Who Is My Mother? The Role and Status of the Mother of Jesus in the New Testament and Roman Catholicism (2001) which discusses this issue, and other issues (e.g., αδελφος/αδελφη in the Greek New Testament and contemporary literature) in great detail.