Angels were certainly not unknown to Israel, and the entire history of Israel occurred under angelic oversight. But nowhere in the Bible is there a cluster of angelic appearances like we find at the beginning of the gospel story.

An angel appears to Joseph to tell him to take Mary as his wife, and Joseph obeys the angel’s instructions. Angels appear again to instruct Joseph to flee from Israel to escape from Herod and to tell him to go home from Egypt back to Israel (Matthew 1-2).

Gabriel appears to Zecharias to announce the imminent birth of John, and the same angel appears again to Mary to announce the birth of Jesus.

An unnamed angel announces the birth of the Christ to the shepherds, and then that angel is joined by the heavenly host praising God for the birth of Jesus (Luke 1-2).

Why are angels suddenly making such frequent appearances? What do these angelic appearances have to teach us about the meaning of the incarnation?

Angels live in heaven, in the presence of Yahweh. They surround Him as His “hosts” or “armies” (Psalm 103:20-21; 148:2), just as a king is surrounded courtiers, retainers, and troops. Angels stand at the ready to be deployed to do Yahweh’s bidding. 

They continuously worship Yahweh in heaven (Revelation 4-5), as the priestly and Levitical choir continuously praised Yahweh with voices and instruments in the temple. Whenever an angel appears on earth, he arrives from heaven. 

When angels appear at the birth of Jesus, they're bringing heaven to earth.  As they sing to the shepherd, “Glory to God in the Highest, and on earth peace, goodwill toward men” (Luke 2:14). Jesus is heaven on earth, heaven become flesh, and so it is fitting that he should be surrounded, as His Father is, by angelic hosts.

We are so familiar with this Christmas scene that we don’t recognize just how unique it is. Nowhere else in Scripture do angelic choirs sing on earth. Nowhere. This is an absolutely unique inbreaking from Heaven to Earth.

Throughout his gospel, Matthew refers to “heaven” and “earth” (6:10; 16:19; 18:18-19; 28:2), sometimes using the phrase “heaven and earth” (5:18; 11:25; 28:18; see Jonathan Pennington, Heaven and Earth in the Gospel of Matthew.). 

Matthew emphasizes that Jesus restores proper order within the creation.  Ultimately, the phrase “heaven and earth” goes back to Genesis 1:1 and 2:1-4. Because of Adam’s sin, heaven and earth are out of sync, estranged, at war. Earth goes its own way, ignoring heaven and defying the God of heaven. There's no longer harmony between the different zones of creation.

Through Jesus the Last Adam, God establishes an outpost of heaven on earth. Because heaven comes to earth, earth will be brought back into harmony with heaven. 

Because of Jesus, heaven is exerting its power on earth again, and reducing earth to heavenly order. Because of Jesus, God’s will is going to be done on earth as in heaven. Jesus is given all authority in heaven and on earth, and because of Him what the church binds on earth will be bound in heaven.

For millennia, there was dissonance between heaven and earth. Earth didn't keep tune with the music of the spheres; earth didn't keep in step with the rhythms of heaven. 

All this changes at Christmas. When Jesus comes as Heaven on earth, He brings the heavenly hosts with Him, so that earth is as full of the music of heaven as heaven is, so that earth’s music will harmonize with that of heaven.

At the heart of this restored harmony is the elevation of man. Angels were created to train human beings to rule the earth. As Jim Jordan says, angels are the drill sergeants who put humanity through basic training. Thus man is, for a little while, lower than the angels.

With the coming of the Son in human flesh, the work of angels is nearly done. They appear in large numbers at the conception and birth of Jesus because this is the time when they turn their authority over to the Son.

One by one, the angels of Christmas throw those crowns down before the Lamb. And as they cast their crowns before the incarnate Son, they cast them before us, so we can take our place beside the enthroned Son of David.