26 And from such members He is not ashamed to assume flesh, who is the framer of those very members. But then who tells us this? The Lord says unto Jeremiah: Before I formed you in the belly, I knew you: and before you came forth out of the womb, I sanctified you. If, then, in fashioning man He was not ashamed of the contact, was He ashamed in fashioning for His own sake the holy Flesh, the veil of His Godhead? It is God who even now creates the children in the womb, as it is written in Job, Have you not poured me out as milk, and curdled me like cheese?
You have clothed me with skin and flesh, and hast knit me together with bones and sinews. There is nothing polluted in the human frame except a man defile this with fornication and adultery. He who formed Adam formed Eve also, and male and female were formed by God's hands. None of the members of the body as formed from the beginning is polluted. Let the mouths of all heretics be stopped who slander their bodies, or rather Him who formed them. But let us remember Paul's saying, Do you not know that your bodies are the temples of the Holy Ghost which is in you?
And again the Prophet has spoken before in the person of Jesus, My flesh is from them: and in another place it is written, Therefore will He give them up, until the time that she brings forth. And what is the sign? He tells us in what follows, She shall bring forth, and the remnant of their brethren shall return. And what are the nuptial pledges of the Virgin, the holy bride? And I will betroth you unto Me in faithfulness. And Elizabeth, talking with Mary, speaks in like manner: And blessed is she that believed; for there shall be a performance of those things which were told her from the Lord.
Source: Catechetical Lectures (New Advent)