Jehovah's Witnesses do not celebrate Christmas because they believe that the holiday is based on pagan traditions, and they do not want to worship anything other than Jehovah. They also believe that the holiday promotes materialism and greed, which goes against their religious beliefs. They prefer to focus on the spiritual aspects of the holiday season, such as spending time with family and helping those in need. Instead of celebrating Christmas, they might celebrate the birthday of Jesus on a different date.