One of the earliest references to a unicorn is about 5000 years ago in ancient China when it was written that a unicorn appeared to the emperor Huang Di as a sign that his reign would be long and peaceful. Also in China it is recorded that a unicorn brought a piece of jade to the mother of the renowned prophet Confucius and laid its head on her lap. She took that as a good omen for what was to come.
Around about the fourth and fifth centuries, merchants would come back from India with stories of a horse with a white body, a red head, bluish eyes and with a horn on its forehead about a cubit long. Sightings of unicorns have also been attributed to Julius Caesar and to Alexander the Great, and there are several clear references to them in the Old Testament of the Bible.
The unicorn represents purity and a Christ-like connection to God and the divine. Although a gentle creature, its horn could be used to protect if needed. So as a symbol it represents your desire to be closer to God, to work towards greater clarity in yourself, and to be protected while doing this.