Even the most modest of Bible readers know that Christ wasn't born on 25th December AND there is no Biblical instruction for us to celebrate His birth. So why do we do it???
To all those who say we can pick and choose what days and man-made festivals we celebrate to honour God, they should bear in mind that God is honoured when we obey HIM.
We don't honour Him by celebrating any day or festival that has its roots in paganism.

However, setting aside personal time AT WHATEVER TIME OF YEAR to give ourselves over to prayer, study, fellowship and worship IS honouring God. But do it for HIM and HIM alone, not because of man-made boozy festivals...