The Zohar in Parashat Bo talks about the recitation of the Shema, also known Kriat Shema. The main thing to do in the recitation of the Shema Israel is to meditate in the unification of Hashem’s names. The Zohar explains that within the Shema recitation there is Hashem Elokenu Hashem. This three words are making reference to  three different Hashem’s names. These three times are three callings to Hashem that are donde through the recitation. The callings are not simple callings but three different levels. 

There are three different aspects within human speech: fire, wind and water. The air is natural within human voice. This air that comes from the lungs has humidity being this the water. And the fire would be the warmth of the body. When they become to be one is what is known as voice. This is the metaphor to understand what does it mean to unify Hashem’s names...

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