Answer: Babylonians spoke Aramaic. We use this language in Kabbalah along with Hebrew. Only those who attained the upper world spoke Hebrew because it is the language of light, and Aramaic is the language of the Kli (vessel), meaning desires that reveal the light.
Both languages are completely identical and at the same time completely opposite to each other. Let’s say “light” in Hebrew is “Ohr,” and night in Aramaic is “Orta.” That is, both languages use the same word but with completely opposite meaning.
Question: What language did Terach, Abraham’s father, speak?
Answer: Terach spoke Aramaic, and Abraham switched to Hebrew. They knew both languages.
As modern publications confirm, from these two ancient languages, which complement each other, a global script developed. After all, both languages are built on coincidence of two forces, bestowal and reception, plus and minus. Precisely from there came the horizontal and vertical elements of the letters that are the basis of the writing in any language.
From the Kabbalah Lesson in Russian 1/22/17