7:14, and the naming of Mary's son by Joseph, are the chief tactics in Matthew's defense against the Jewish charge that Jesus was the illegitimate son of Mary.40 (religion-online.org)
As for Jordan, he's also excellent, taking his easy charisma and charm to a darker place, letting you understand the pain of being the illegitimate child of essentially a folk hero. (awardscircuit.com)
Its use in this Gospel passage shows that if a man and a woman are in fact married, the bond is inseparable, but if they entered into marriage illegitimately, i.e. not that they entered an illegitimate union with a third party, but that if their own sexual union was illegitimate because of impediments (such as age, relation or bigamy etc.), then their marriage was never lawful, never a valid marriage, and that they are, therefore, free to enter into a new valid marriage. (faith.org.uk)