The tradition of using lights during Christmas most likely originated in Germany during medieval times with the burning of the Yule log. This was done during the short, dark days of winter to help bring light into the home.
Edward H. Johnson put the very first string of electric Christmas tree lights together in 1882. Johnson, Edison's friend and partner in Edison's Illumination Company, hand-wired 80 red, white, and blue light bulbs and wound them around his Christmas tree.
Biblically, sin is equated with darkness, and the righteousness made possible through the Savior, Jesus Christ, is linked with light. Jesus said in John 8:12, “I am the light of the world. Whoever follows me will never walk in darkness, but will have the light of life.”