The Zohar refers to Moses being the only prophet to speak “mouth to mouth” with The Holy One.
They talk about this communication being through the Sh’ma and the sephirot here inside the representational “mouth” of Hashem with the colors of the four worlds Kabbalah says we live in simultaneously. The Zohar also says that a two-edged sword with the Yud Heh Vov Heh surrounding it emerges from his lips to cut through hypocrisy clearing a way for truth, compassion, forbearance and peace.