Let all together praise our God before His glorious throne;
Today He opens heav'n again to give us His own Son
To give us his own Son.
God opens heaven to send his Son. We see the echoing of His glory and the joy of His incarnation as the announcement is made to the shepherds on that Christmas night:
“Fear not: for, behold, I bring you good tidings of great joy, which shall be to all people.
For unto You is born this day in the city of David a Savior, which is Christ the Lord.
And this shall be a sign unto you; Ye shall find the babe wrapped in swaddling clothes, lying in a manger.”
At this announcement of the opening of heaven to send the Savior, a multitude of the host of heaven also spill through the door. Unable to hold back their excitement over God's marvelous work Heaven overflows onto Earth with the praise of the Lord and the angelic song fills the night:
“Glory to God in the highest, and on earth peace, good will toward men.”
The problem was that heaven was not always open. The way had been barred by sin as Adam and Eve had seen in the Garden of Eden. There and angel also stood making an announcement, but his message was not good news. With flaming sword in hand, he barred the way back into paradise. By sin and rebellion against God and His Word Adam and Eve were expelled from the garden. They left the garden by their disobedience. It is only a false misleading dream to think that we could reenter paradise by any act of our obedience. It could never succeed. All such efforts are doomed to fail. Thus the angel stands guard. Man must not eat from the tree of life while in his sin. But:
He undertakes a great exchange, Puts on our human frame,
And in return gives us His realm, His glory and His name,
His glory and His name
This great exchange is the Lord's plan to open the way to heaven and at the resurrection of all flesh to a restored paradise. No one from our side could open the door, but from the holiness of heaven, Christ could. Entering our sin soaked world had a great cost for Him, though; as soon and he entered the world he bore on his infant frame the full weight of all our sin. But the door is open:
He is the key and He the door To blesséd paradise;
The angel bars the way no more. To God our praises rise,
To God our praises raise.
The first president of our Synod, C. F. W. Wather, concludes a Christmas sermon this way:
O my dear hearers, in conclusion I therefore call you once more: Rejoice! The Savior is born; heaven is open for you. Now let none of you remain irresolute and hesitant as you stand before the open gates of heaven. Do you perhaps want to remain outside for the sake of the joy that the world and its sin and vanity gives you? Oh, consider this: This joy is nothing but apparent joy, and its end is everlasting mourning! Or do you perhaps not want to enter because of your many and great sins? Oh, think about this: The gates of heaven have been opened so wide precicely for the sake of sinners, for gret sinners! Or do you think you must first do something in order to be worthy of it? Oh, concider: As long as you remain outside, you remain unworthy; you will become worthy by going in! O, therefore, believe the joyful Christmas message I have brought you today. Then you also today will go throug it as through an open gate of heaven, into heaven opened wide for you today. And when onde day your bodily eye is closed in death, then the eye of your soul will behold all the glory of heaven. You will “rejoice with unutterable … joy” [1 Pe 1:8], and “no one will take your joy from you” [Jn 16:22].1
1Selected Writings of CFW Wather: Selected Sermons, Henry J. Eggold, translator (St. Louis: Concordia Publishing House, 1981, as printed in Concordia Pulpit Resources, vol 18, part 1, p. 57