Shortly after an angel of the Lord appeared to the shepherds on the night of Christ's birth, the Scriptures say "a multitude of the heavenly host [angels, were] praising God, saying, "Glory to God in the highest, and on earth peace among men with whom He is pleased." The angels of God celebrated the birth of Jesus! So, if we celebrate Jesus' birth with singing (e.g., "Joy to the World," "Silent Night," "Away in a Manger,") we are following the pattern laid out for us by the angels.
Now, as I already mentioned, celebrating Christmas is not something God commanded us to do ("Celebrate my Son's birth once a year!") but that may be why our celebrating Christ's birth might bless Him all the more. We are celebrating His gift out of love for Him, not because we have some command to obey, but because we freely want to celebrate and thank Him for His gift. When my kids celebrate the fact that I'm their Dad by making me a card, giving me a gift, or telling me something kind, I don't frown and say, "Stop it! I never commanded you to celebrate. Return the presents! Stop the kind comments!" No. I rejoice all the more that they would freely decide to celebrate and rejoice all on their own.
As you, as a born again follower of Christ, celebrate Jesus this Christmas, you can rest assured that God is delighted in your celebration. The angel told the shepherds, "Do not be afraid, for behold I bring you good news of a great joy [sounds like reason to celebrate] which shall be for all the people [sounds like you and me!]; for today in the city of David there has been born for you a Savior, who is Christ the Lord." What a reason to celebrate not just this week, but every day!
I pray you have a very blessed, Christ-focused Christmas celebrating with the angels "His indescribable gift!" (2 Cor. 9:15).