The Jewish Month of Iyar
According to Sefer Yetzirah, each month of the Jewish year has a letter of the Hebrew alphabet, a zodiac sign, one of the twelve tribes of Israel, a sense, and a controlling limb of the body that correspond to it.
"Iyar" is the second of the twelve months of the Jewish calendar. In the Bible, the month of Iyar is called the month of "Ziv" (radiance). Iyar is also cognate to light. The month of Iyar is commonly referred to as the month of (natural) healing, for its name is an acronym for "I am G-d your Healer" (Exodus 15:26).
"Vav" is a link. Iyar links together the two months of Nissan and Sivan (by the power of "sefirat haomer," which begins in Nissan, continues throughout Iyar, and concludes in Sivan), the month of redemption and the month of the giving of the Torah. Only these three months are referred to in the Torah as the first, the second, and the third month of "the Exodus of Israel from Egypt."
Mazal: "Shor" (Taurus-ox).
The "shor" (the left face of the Divine Chariot) represents the spiritual origin of the "animal soul" of man. The month of Iyar is the month that man rectifies his animal soul, refines his innate character traits (each day of "sefirat haomer"), as he prepares to receive the Torah in Sivan. In Hebrew, the root "shor" also means to look or observe. Iyar is the month of introspection for the sake of self improvement.
Isaachar is the scholarly tribe of Israel. The Sanhedren was mostly composed from the tribe of Isaachar. In particular, Isaachar was the master of the "secret" of the Jewish calender, as is said of him: "knowers of understanding the times." His basic nature is contemplative and he serves as the "advisor" to his brethren, the tribes of Israel (in particular to the king, Judah).
Thought here implies contemplation and introspection. It also signifies the power of calculation (as in the calculation of the calender). This is the month of counting ("sefirat haomer"). The root "to think" in Hebrew "chashav" means "numerical calculation," "cheshbon."
Controller: Right kidney.
Our sages say "the kidneys give advice." In particular, the right kidney relates to spiritual advice or introspection. The kidneys act similarly to the "conscience," as is said "by night my kidneys chastise me." This refers to the "chesbon nefesh" (introspection) of the month of Iyar.