You're correct of course, concerning the date and the historical "Christ mass." There is no scriptural basis for this or any special holiday celebrating Christ's birth. But opinion has little to do with the objective message of Scripture, particularly the New Testament, which is from beginning to end a record and explanation of the Incarnate Word and His accomplishment: salvation for sinners-which, according to Scripture, will be celebrated for all eternity. Philippians 2:5-11, which describes the Incarnation and the Father's response to the work of the Son, is an example. Whether or not we should celebrate the historical Christmas holiday is a personal matter, but the value of the Incarnation is the message of the Bible.