11 By these words the divine Master is speaking not of bodily impediments to marriage, but of a resolution freely made to abstain all one's life from marriage and sexual pleasure. For in likening those who of their own free will have determined to renounce these pleasures to those who by nature or the violence of men are forced to do so, is not the Divine Redeemer teaching us that chastity to be really perfect must be perpetual?
Source: Sacra Virginitas (Vatican.va)