According Sefer Yetzirah, Tuesday is ruled by the sun. The corresponding Hebrew and Celtic archetypes are Yaakov and Belenos, respectively.
Belenos is a "Romanized" form of the Celtic name Beli Mawr (בלי מאור), where beli means "shining" (Celtic) and mawr means "of light" (Celtic and Hebrew).
Alternatively, in Hebrew, beli can mean "without" - like within the word "belimah" of Sefer Yetzirah (page 25). Thus, Beli Mawr (בלי מאור) can mean both "shining of light" and "without light" simultaneously, depending on whether one is looking through Celtic or Hebrew consciousness. Consequently, in this archetypal name, we have both a kav (a "shining" of light as in Celtic myth and Jewish kabbalah) and a Lamp of Darkness (Botzina de Kardenuta, or the tzimtzum of Jewish kabbalah) existing together in harmony.
Interestingly, both Yaakov and "the giving of the Torah" are represented by the kav in Jewish kabbalah. This association is more in line with the meaning of the Celtic (kav) interpretation of Beli Mawr as opposed to the Hebrew (tzimtzum) interpretation. This makes Hebrew Yaakov and Celtic Beli Mawr one and the same essence, both possessing Torah, and each the "reverse vision" of the other.