Sivan is the month of unity. It is the third month of the liturgical calendar and the ninth on the civil calendar. This Hebrew month corresponds to the Gregorian months of May and June. It is the final month of Spring before the Wheel of the Year turns to Summer.
Sivan is represented by the constellation Gemini- the twins or teomim in Hebrew. Shavuot is the holiday that occurs during Sivan, and it is the remembrance of the Hebrews receiving the Torah and becoming a nation. The teomim of Gemini are represented here by the twin tablets of the covenant that Hashem gave to Moses. The twins are also represented by the connection in the hearts and minds of all Israelites when they determined to receive and accept Torah.
In general, Gemini is known as the most talkative and communicative of astrological signs. We can see this represented by the planet Mercury which rules the month of Sivan. It is the planet of communication. In Greek mythology, Mercury was the messenger of the gods. He was important for both sending and receiving messages- twin aspects of communication.
The letters for Sivan are zayin (ז) and reysh (ר). Zayin corresponds to the month of Sivan and reysh to the planet Mercury. If you combine the letters, you get the word Raz (רז), meaning – secret. We must balance our desire for truth with the need for secrets and vice versa.
When we talked about Iyar, we learned that Issachar is the tribal leader for the month. For Sivan, it’s Zebulun. These two tribes shared a special bond. They were born one after the other to Leah, they inherited adjacent lands, and their months follow one after the other. We saw that Issachar was a tribe of scholars. Those scholars were supported monetarily by the merchants of Zebulun who agreed to split their material wealth. In exchange, Issachar split their spiritual wealth with Zebulun.
It is relatively easy to see why I say that unity is the overarching theme of Sivan. We have twins supporting one another as well as a nation in unity to adopt a new system of governance. We have brothers so closely associated with one another that they seem to be twins. We have the twin aspects of communication. May we merit such unity with others.