There’s no shortage of biblical objections when it comes to Mary’s perpetual virginity. A common one comes from Luke 2:7, where Luke writes, “And she gave birth to her first-born son [Gk. prōtotokos] and wrapped him in swaddling cloths.”
Some Christians argue that the word “firstborn” itself necessarily implies there were other children born of Mary. If there was a firstborn, so the thinking goes, then there must have been a second-born.
Other Christians, however, distance themselves from the necessary implication of the word prōtotokos and argue that even though the word can imply either “other siblings” or “the first to open the womb,” Luke elsewhere in his Gospel gives us reason to think he intends the “other siblings” meaning.
Thus, we have two versions of this objection from Luke 2:7, the former being the less sophisticated. Let’s deal with that one first.
The main problem with this version of the argument is that it assumes that the term “firstborn” itself necessarily implies there were other siblings born of Mary. But this is patently false.
We can start with the Bible. Consider, for example, Hebrews 1:5-6: “To what angel did God ever say, ‘Thou art my Son, today I have begotten thee’? Or again, ‘I will be to him a father, and he shall be to me a son’? And again, when he brings the first-born into the world, he says, ‘Let all God’s angels worship him.” Does this mean that God the Father had other sons, since Jesus is referred to as the “firstborn” of God? Of course not!
Exodus 13:2 is another example: “Consecrate to me all the first-born; whatever is the first to open the womb among the people of Israel, both of man and of beast, is mine.” Does this mean that the parents had to wait until there was a second-born to consecrate the first to the Lord? Nope!
As we see in these examples, “firstborn” doesn’t necessarily mean there were others. It also can mean “the first to open the womb.”
St. Jerome makes this argument in his The Perpetual Virginity of Blessed Mary, writing,
The word of God compels me to dedicate to God everything that opens the womb if it be the firstling of clean beasts: if of unclean beasts, I must redeem it, and give the value to the priest (12).
The Protestant biblical scholar Victor Hamilton joins ranks with Jerome, writing in Exodus: An Exegetical Commentary, “To say that Jesus is Mary’s prōtotokos is simply to say Mary had no child before she gave birth to Jesus” (14).
Since the Bible uses “firstborn” without implying a second-born, this argument from Luke’s mere use of the term “firstborn” doesn’t prove Mary was not a perpetual virgin, since Luke could be using it to signify the first to open the womb.
Well, which is it? This leads us to the more sophisticated version of the argument.
In his 2022 debate with Trent Horn, Protestant apologist Steve Christie acknowledged that prōtotokos can be used either to imply other siblings or the first to open the womb. But he thinks we have reason to conclude that Luke intended the “other siblings” meaning. Here’s what he argued in the debate:
If Luke was communicating Jesus was Mary’s only child, he would’ve used the Greek word [monogenēs] translated “only begotten,” rather than prōtotokos, like he did elsewhere in his Gospel, such as in Luke 7:12, 8:42, and 9:38.
For Christie, therefore, that Luke uses prōtotokos instead of monogenēs implies that Luke intended the “other sibling” meaning versus the “first to open the womb” meaning.
The problem with this counter is that Christie shoots at the wrong target: the claim that Luke was communicating that Jesus was Mary’s only child. In other words, he’s attacking a straw man.
Recall his argument: if Luke had intended to communicate that Jesus was Mary’s only child, then he would’ve used the Greek word monogenēs, translated “only begotten.”
Notice that Christie creates an expectation for the use of monogenēs, making its absence seem to be a defeater of Mary’s perpetual virginity. But there is no need for Luke to use monogenēs if he’s not intending to communicate that Jesus was Mary’s only child. Perhaps he intended to communicate something else that wouldn’t necessitate monogenēs (only begotten). If this were the case, then Christie’s objection would have no persuasive force.
One plausible candidate for that “something else” that Luke was intending to communicate is the simple point that Jesus was the first to come through the womb of Mary. This would be true regardless of whether there were other siblings or not.
But there is another plausible candidate. As Trent correctly pointed out in the debate, the context reveals that Luke’s focus was something entirely different—namely, Jesus’ “firstborn” status as being consecrated to God. Verses 22-23 make this clear:
And when the time came for their purification according to the law of Moses, they brought him up to Jerusalem to present him to the Lord (as it is written in the law of the Lord, “Every male that opens the womb shall be called holy to the Lord”).
Luke explicitly quotes Exodus 13:2 within the same chapter that speaks of the law to consecrate to God the first to open the womb—i.e., the “firstborn.” Given this context, we can conclude that by “firstborn,” Luke intended the “first to open the womb” meaning.
Christie counters this by saying that Luke 2:22-23 is a different event from what occurs in Luke 2:7. Thus, we can’t interpret “firstborn” in verse 7 considering what he talks about in verses 22-23.
But who says we can’t interpret “firstborn” in verse 7 as reference to the consecration of the “firstborn” in verses 22-23? If the term is frequently used as such within the Jewish milieu, which it is, and Luke speaks of Jesus’ consecration as the first to open the womb as the culmination of the same infancy narrative that he kicks off with the use of the term, then it’s exegetically reasonable to interpret “firstborn” in verse 7 in light of the consecration in verses 22-23.
Secondly, even if we concede that Christie blocks our appeal to the consecration in verses 22-23, we still can appeal to either the possibility of the simple use of the term to signify the first to open the womb or the Jewish use of “firstborn” as a reference to the firstborn consecration, thereby creating an impasse as to which meaning Luke intends. It could refer to “other siblings,” but it could also refer either simply to the first to open the womb or the consecration of the first to open the womb. Given such ambiguity, and without further evidence to tip the scales, Christie wouldn’t be able to appeal to the “firstborn” text as a defeater of Mary’s perpetual virginity.
In sum, Luke’s use of prōtotokos in 2:7 does not, by itself, establish that Mary bore other children, since Scripture and Jewish usage regularly employ the term to signify the first to open the womb without implying subsequent births. Also, the appeal to monogenēs fails, because it assumes that Luke intended to assert Jesus’ status as Mary’s only child, when the context instead points to legal and cultic concerns surrounding firstborn consecration.
At best, then, Luke 2:7 is ambiguous, and an ambiguous text cannot overturn the historic Christian belief in Mary’s perpetual virginity.