The text of this aria comes from the words of the Jewish prophet Malachi.

Show Synopsis:
Handel's Messiah has been described by the early-music scholar Richard Luckett as "a commentary on [Jesus Christ's] Nativity, Passion, Resurrection and Ascension", beginning with God's promises as spoken by the prophets and ending with Christ's glorification in heaven.[15] In contrast with most of Handel's oratorios, the singers in Messiah do not assume dramatic roles, there is no single, dominant narrative voice, and very little use is made of quoted speech.

Fun Facts:
1) These are is the nineteenth section of the second part of Handel's famous Messiah, the prophecy of Christ's birth. 
2) The text of the Messiah was compiled from the text of the King James Bible and Psalms of the Book of Common Prayer.