The assertion in the gospels of Matthew and Luke that Jesus was born of Mary without the intervention of a human partner. The pregnancy was initiated by the Holy Spirit (Matt. 1: 18; Luke 1: 35). The earliest writers in the NT (Mark and Paul) show no knowledge of such a virginal conception, and it is suggested that the narratives are a midrash on the LXX of Isa. 7: 14 which prophesies a birth from a ‘virgin’ (in the Greek). The Greek parthenos was used to translate the Hebrew almah, which means a ‘young woman’, and is so translated at Isa. 7: 14 by NRSV, REB, NJB, thus correcting the ‘virgin’ of AV, RV. But modern translations of Matt. 1: 23 correctly translate the Greek parthenos by ‘virgin’ because Matthew is quoting the LXX. According to the Palestinian Talmud there was a second category of virginity; it was applied to any girl before she had reached puberty and also could possibly become pregnant—thus still remaining ‘a virgin’. As early as the 2nd cent. CE the Jewish controversialist Trypho was pointing out that the Hebrew did not mean a virgin but that Isa. 7: 14 was referring to the natural birth of Hezekiah. Indeed the LXX went out of favour with Greek-speaking Jews, who opted for the literal translation by Aquila in the early 2nd cent. CE. Later in the 2nd cent. the pagan philosopher Celsus claimed that Jesus' father was Panthera.

The narratives in Matthew and Luke are very different from the exuberant birth stories of heroes in Hellenistic literature or the birth of the emperor Augustus, mentioned in Suetonius' Life (94). But since historical enquiries cannot settle the truth or otherwise of the gospels' accounts, there are also theological and devotional arguments. In favour of the traditional doctrine it is argued that it is appropriate as a means by which God made a decisive break with the old, sinful humanity and inaugurated in Jesus a new, untainted humanity. The miracle of the conception came to be regarded as a sign of the divine nature of Jesus; in Filippo Lippi's The Annunciation, the use of light links the creation of light in Gen. 1: 2 with the conception of Christ. It is a kind of poetic expression of a theological truth, while the birth itself indicated true humanity (and as an argument against Docetism it was included in the creeds). On the other hand, some modern theologians argue that the doctrine must imply that the humanity of Jesus was somehow impaired, since with only one parent he could not have been a fully male human being. This is also ‘truth’; if Jesus was provided miraculously with DNA, specially created by God, with no human ancestry, how did he have a human inheritance, of the house of David (Matt. 1: 17, 20; Rom. 1: 3)?