In 107, Ignatius of Antioch described the virginity of Mary as "hidden from the prince of this world… loudly proclaimed, but wrought in the silence of God".[2] The affirmation of the doctrine of Mary's virginity before, during, and after the birth of Jesus was the principal aim of the early second century work, the Protoevangelium of James (c. 120-150).[3] The work, concerned with the character and purity of Mary, claims that Joseph had children from a marriage previous to Mary.[4] However, the text does not explicitly assert the doctrine of perpetual virginity, the earliest such surviving reference being Origen's Commentary on Matthew,[5] where he cites the Protoevangelium in support.
By the fourth century, the doctrine is well attested.[6] Athanasius described Mary as "Ever-Virgin",[7] as did Epiphanius.[8] Hilary argued in favor of the doctrine,[9] and to this may be added Didymus,[10] Ambrose,[11] Jerome,[12] Siricius[13] and others. However, it cannot be said that unanimity existed in antiquity concerning the doctrine, as it was denied by Tertullian,[14] and Jovinian's teaching that childbirth ended Mary's physical virginity had to be condemned by a synod of Milan in 390.
Further important statements of the belief include the Lateran Synod of 649, Thomas Aquinas's teaching that Mary gave birth painlessly in miraculous fashion without opening of the womb and without injury to the hymen,[15] Pope Paul IV's Cum quorundam of 7 August 1555 at the Council of Trent,[16] and most recently the statements in the current catechism.[17]
During the Protestant Reformation, the doctrine came to be questioned, although such notable reformers as Martin Luther,[18] Huldrych Zwingli,[19] John Calvin,[20] and John Wesley[21] accepted its veracity.[22] However, the absence of clear Biblical statements expressing the doctrine, in combination with the principle of sola scriptura, kept references to the doctrine out of the Reformation creeds. Additionally, the tendency to associate veneration of Mary with idolatry[23] and the rejection of clerical celibacy[24] lead to the eventual denial of this doctrine amongst most Protestant churches. Lastly, many Protestant communities cite Biblical passages that refer to the "brothers" of Jesus (see below, see also Desposyni).
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You can dispute the PV of the Theotokos if you like, but the historicity of the belief is ancient and well documented.