The double nature of Advent is reflected in this text, in which we remember Christ's first coming even while praying for his return. Stanzas 1 and 2 recall Advent prophecies in the Old Testament; stanza 3 speaks of Christ's birth and kingdom, and stanza 4 is a prayer for Christ's rule in our hearts.
The phrase “long-expected” and “the Savior promised long” are descriptors of Jesus and are familiar terms to many Christians. These words speak of generations who waited while centuries passed. Our World Belongs to God, paragraph 23 also uses such terminology in calling him the “long-awaited Messiah.” And Belgic Confession, Article 18 professes that this all happened only “at the time appointed.”