Old Kabbalah have found connections between the twelve signs and the Hebrew letters. According to Kabbalah, each letter of the Hebrew alphabet represents some qualities and connections to the 10 spheres/emanations:
כתר Keter, חכמה Chokhmah, בינה Binah, חסד Chesed, גבורה Gevurah, נצח Netzach, תפארת Tiferet, הוד Hod, יסוד Yesod, מלכות Malchut
Which can be translated as: Crown, Wisdom, Understanding, kindness/favor, Gracefulness, Eternity, Splendor, Foundation, Kingship.
for example, א, the Hebrew Aleph or first letter, is connected to כתר Keter, Crown emanation. ב, the Hebrew Bet or second letter, is connected to חכמה Chokhmah , Wisdom emanation. And so on until ת, the Hebrew Tav or the last letter.
12 signs and their letters
as seen in these pictures:
the old Hebrews knew of 7 rulers ruling the 12 signs: Saturn, Shabtay, ruled Capricorn and Aquarius; Jupiter, Tzedek, ruled Sagittarius and Pisces; Mars, Ma’adim, ruled Aries and Scorpio; Sun, Chama, ruled Leo; Venus, Noga, ruled Taurus and Libra; Mercury, Kochav, ruled Gemini and Virgo; and finally Moon, Levana, ruled Cancer. Each of the signs and their rulers was connected to two of the Hebrew alphabet letters, like this:
Saturn, Shabtay, was represented by the letter ב, Bet; Capricorn and Aquarius, being ruled by it, got the letters בע for Capricorn and בצ for Aquarius.
Jupiter, Tzedek, was represented by the letter ג, Gimmel; Sagittarius and Pisces, being ruled by it, got the letters גס for Sagittarius and גק for Pisces.
Mars, Ma’adim, was represented by the letter ד, Dalet; Aries and Scorpio, being ruled by it, got the letters דה for Aries and דנ for Scorpio.
Sun, Chama, ruled Leo; this sign got the letters כט.
Venus, Noga, was represented by the letter פ, Peh; Taurus and Libra, being ruled by it, got the letters פו for Taurus and פל for Libra.
Mercury, Kochav, was represented by the letter ר, Reish; Gemini and Virgo, being ruled by it, got the letters רז for Gemini and רי for Virgo.
Moon, Levana, ruled Cancer; this sign got the letters תח.
the only combinations of letters with a meaning in Hebrew is the Gemini combination: רז means secret.
meaning of the different emanations the letters belong to
Here you can find the Hebrew letters and their meaning according to Kabbalah and the different spheres/emanations they belong to (in Hebrew). warning: it is not only in Hebrew, it is also very complicated because while some of the letters are connected to 1 emanation, some are related to 2 and more. Also the references to the elements that are known in modern western Astrology: water, fire, earth and air – are different in this old eastern approach to Astrology, in a way you end up with Aquarius being a partly earth sign.
Strengthening / Empowering a sign affect by wearing the letters
One kabalic way of making a sign more dominant and empowering its affect on you is wearing the letters of the sign in a talisman held on the neck. According to the belief, in order for this to really work the letters should be written by a Mekubal, a healer, an expert in Torah and a well-taught person, sometimes a Rabi. The Mekubal makes the talisman with the letters of the chosen sign and the letters radiate the energy of the sign.
According to the belief, it is not only useless but also dangerous to write letters by yourself without consulting a Mekubal.
The energies of the different signs, radiated from the letters in the talisman, help to balance an unbalanced chart or other unbalanced energy.