:See [http://philologos.org/__eb-jbl/brethren.htm ''The Brethren of the Lord'', J. B. Lightfoot, 1865, <small>Commentary on the Epistles of St. Paul, Dissertation.</small>]. Dr. Lightfoot (a Protestant) discusses in detail the ''Epiphanian'', the ''Helvidian'', and the ''Hieronymian'' ([[Jerome]]/Jeromian) theories of the relationship of the brothers of the Lord.
:*The ''Epiphanian'' theory of Epiphanius of Salamis (c. 315-403) maintains that no blood relationship existed; that these brethren were in fact sons of Joseph by a former wife, before he espoused the Virgin; and that they are therefore called the Lord's brethren only in the same way in which Joseph is called His father, having really no claim to this title but being so designated by an exceptional use of the term adapted to the exceptional fact of the miraculous incarnation.
:*The ''Helvidian'' theory, advanced by certain persons (such as [[Tertullian]], who does not directly discuss the issue, and in particular, [[Helvidius]], who lived in Rome at the time of Jerome toward the close of the fourth century) argues that the obvious and most literal meaning of the term was the correct meaning, and that these brethren were the Lord's brethren as truly as Mary was the Lord's mother, being her sons by her husband Joseph (uterine relationship, born from her womb from the seed of Joseph by natural marital conception).
:*The ''Hieronymian'' theory, proposed in or about the year 383 by Jerome, at the instigation of 'the brethren' wrote a treatise in reply to Helvidius, in which he maintains that the Lord's brethren were His cousins after the flesh, being sons of Mary the wife of Alphaeus and sister of the Virgin.
:Dr. Lightfoot asserts in his dissertation, ''The Brethren of the Lord'' (1865), that the most devastating argument against the Helvidian theory is to be found in the prevailing first century Jewish cultural bonds of the most paramount and inviolable familial duties rooted in "the most sacred ties of natural affection" ([https://www.biblegateway.com/passage/?search=Exodus+20%3A12&version=KJV Exodus 20:12]; [https://www.biblegateway.com/passage/?search=Leviticus+19%3A2-3&version=KJV Leviticus 19:2-3]; [https://www.biblegateway.com/passage/?search=Deuteronomy+21%3A18-21&version=KJV Deuteronomy 21:18-21]; [https://www.biblegateway.com/passage/?search=Deuteronomy+27%3A16&version=KJV 27:16]; [https://www.biblegateway.com/passage/?search=Proverbs+30%3A11&version=KJV Proverbs 30:11] and [https://www.biblegateway.com/passage/?search=Proverbs+30%3A17&version=KJV 17]) and in Jesus' entrusting of his mother to the son of another woman, the son of Zebedee, in [https://www.biblegateway.com/passage/?search=John+19%3A25-27&version=KJV John 19:25-27:]