Therefore will I divide him a portion with the great, and he shall divide the spoil with the strong; because he hath poured out his soul unto death: and he was numbered with the transgressors; and he bare the sin of many, and made intercession for the transgressors.
Isaiah 53:12
That is the "Reason for Christmas" that Jesus was born to "bare the sins of many and make intercession for the transgressors." We have so much to be thankful for, but most of all the salvation we are afforded through what Jesus did for us. Please don't lose sight of that during your Christmas celebrations.