St. Jerome (347–420), the renowned translator of the Bible into Latin (the Vulgate) went so far as to say: “You say that Mary did not remain a virgin? Well, I say that Joseph himself was a virgin, and that the virgin Christ was born from a marriage of virgins.9
Well, they may have both been virgins before consummation of their marriage so it was a marriage of virgins. And aren't we all virgins at birth. So he's not lying.