I am an unapologetic Christian. I believe in the triune God of the Christian Scriptures. I believe in the virgin birth of Jesus Christ, that He lived a sinless life, that He died on a cross outside of Jerusalem, and I believe that He rose again on the third.
Was Jesus born on December 25? Probably not, but it does not matter. Far more then a millennium ago Christians chose to celebrate the birth of our Lord on this day. I believe it is good that we do so.
It is necessary to celebrate Christmas? No. It is not, as St. Paul wrote, "One person esteems one day above another; another esteems every day alike. Let each be fully convinced in his own mind. He who observes the day, observes it to the Lord; and he who does not observe the day, to the Lord he does not observe it. He who eats, eats to the Lord, for he gives God thanks; and he who does not eat, to the Lord he does not eat, and gives God thanks. " (Rom. 14:5-6)
There are "Christians" who condemn and try to tear down the celebration of Christmas. If they can not celebrate this day in good faith, than they should not do so, but neither should they try to drag others into their weakness. They are free to not celebrate, just as I have liberty in Christ to celebrate his birth near the winter equinox as most my Christian brothers and sisters have done for more than 1500 years.
We have liberty in Christ in matters such as this. It is sad to see people bind their own consciences so that they can not enjoy Christ in His fullness.