When you put up that tree, tack a wreath on the door, and maybe hang mistletoe from the lintel, what are you signifying? John Williamson, in “Christmas Greenery” in the Dallas Morning News (December 6, 1986), encapsulates the pagan origin of decorating with evergreens:
Evergreen trees were important fertility emblems for pre-Christian ceremonies marking the winter solstice. People from ancient societies believed that by decorating their homes and temples with evergreen plants, such as holly, ivy and mistletoe, they were helping to carry the diminished sun through a critical period. . . . Mistletoe was the most sacred plant of the Druids. . . . [It] was given great reverence . . . because it grows on the venerated oak. The custom of kissing under the mistletoe comes from the ancient idea that mistletoe is the oak’s genitals. And so it was believed that an embrace under its glistening berries was sure guarantee of a fruitful union. . . . The decoration of Christmas trees is a survival of pagan tree veneration. . . . For centuries before Christianity, holly was . . . used . . . for celebrating their midwinter Saturnalia.
While all the greenery in a home decked out for Christmas is beautiful to look at, these customs have nothing at all to do with Christ. In fact, they are sheer paganism directly descended from ancient rites practiced long before Jesus‘ birth (see Jeremiah 10:1-5). Do you really want to give the impression that you are worshipping a tree? Or that you desire a fruitful union because you give someone a kiss under the mistletoe?