Rune *kenaz/kaunan symbolizes the “light of knowledge.” The original meaning of *kenaz though is “PINE” or the TORCH of flammable pinewood.
*Kenaz, from the Old Norse kaun is a cognate of the Old English cēn. The Old Indo Iranian term for PINE is a cognate as well, where k is replaced with s. The Russian word for pine sosná comes from the same ancient root, (See Didier Calin.)
An Old English rune poem says: Cen byþ cwicera gehwam, cuþ on fyre blac ond beorhtlic, byrneþ oftust ðær hi æþelingas inne restaþ.
The torch is known to every living man / by its pale, bright flame; it always burns / where princes sit within (Courtesy of Didier Calin.)
The Zoroastrian sacred lore uses the imagery of the torch, and lighting one flame from another, to indicate the immortal spark of the amešá/amertá spentás, the Auspicious or Brilliant Immortals of Ahûrá Mazdá.
The nature of the Immortal Gods is likened to the fire of the TORCH that takes many wondrous forms. The TORCH speaks in words of the eternal flame, the same message of “brilliant energy, inspiring creativity, and intense passion.”
The eternal flame is a long-standing tradition in ancient Zoroastrianism. The eternal flame in the Mazda worshipping religion of the ahuras, must be kept alive only by the burning of the sacred wood. Avesta talks of the ûrvázištá fire or fire that is hidden in ûrvar or trees, (Compare with Latin arbor “tree.”)
Cypress and Pine trees (káj in Persian) play a major role in the ancient Zoroastrian religion. For the evergreen trees represent eternal life, and pinecones specifically represent the continuity and renewal of vital energy and sacred knowledge.
Interestingly, the pine tree was the sacred tree of Roman Mithraism. Romans themselves called Mithraism as the Parsi or Persian Religion, and only knew it by the latter name. Mithraism became the most widespread religion in ancient, pre-Christian Rome. During the Roman holiday of winter solstice (Dec. 17-25th), the pine trees were decorated with shining ornaments according to the Mithraic rites.
Pine trees were also one of the symbols of the Germanic mid-winter festival of Yule.
In conclusion, I shall add that in ancient Druid rituals, pine was burned to commemorate the changing of seasons and to bring back the vitality/energy of the sun. This tradition is kept alive to this day in the Scottish countryside.