Now the birth of Jesus Christ happened this way: When his mother Mary was espoused to Joseph, before they came together, she was found to be with child of the Holy Spirit.
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Remigius of Rheims
Yet it might be referred to the foregoing in this way, The generation of Christwas, as I have related, thus, “Abraham begat Isaac.”.
Or the word “come together” may not mean carnal knowledge, but may refer to the time of the nuptials, when she who was betrothed begins to be wife. Thus, "before they came together,” may mean before they solemnly celebrated the nuptial rites.