Bernard of Clairvaux

Thus animated to cast out fear by a spirit of faith, she said to the angel: "How shall this be done, for I know not man?" She doubts not the fact, but only inquires about the manner of its accomplishment. She says not "Will it be done?" but "How will this be done?" As if she would say: "Since my Lord knows, and my conscience bears me witness, that His handmaid has made a vow to know no man, by what law shall it please Him to work this wonder? If I must break my vow that I may bring forth such a Son, I rejoice on account of the Son, but I grieve because of my vow. Nevertheless, His will be done. If, however, as a Virgin I may bring forth this Son and it is not impossible if He so will it then I shall know that He hath had regard to the humility of His handmaid. How, then, shall this be done, for I know not man?"