This is a great story with a great fundamental message about the true meaning of Christmas. Some of the characters are a bit predictable and one-dimensional (the self-serving lead pastor, the legally pious civil liberties activist), but they are tolerable as the main characters navigate and grow through the challenges before them.
Unfortunately, this story and its message are marred by the potshots taken at an alleged war on Christmas. No local government would outlaw a creche on church property. None. And no school would send home a student for the phrase "Reason for the season". Those are strawman situations that the movie piously knocks down with a sledgehammer. More realistic challenges handled more eloquently would have made this a much better movie.
The movie's characters frequently treat everyone as if they're Christians, whch is also unrealistic. Christians live in a world with people of other religions, which is why businesses call things a holiday party or a winter gala, and we all need to respect other people's religious choices. This movie's Christian characters want their choices respected; so they should treat others (of other religions) as they would want to be treated.
Once one gets past the cheap shots and the tunnel vision, however, this movie has a great message for those who do celebrate or want to celebrate Christmas.