This is the mystical meaning of the verse, “And Avram was 75 years old upon his leaving חָרָן-Charan.” (Bereishis 12:4)
On a simple level, Charan was the name of the place where Avram lived with his father Terach before continuing on to travel to the land of Kenaan. The Alter Rebbe is explaining Avram to mean the lofty Wisdom Above as it descends into the Emotive Attributes of Ze’eir Anpin. This is the stage preceding its descent into Malchus (the Land Hashem will show him).
The word “חָרָן-Charan” comes from the phrase “חרון אף-burning anger.” Meaning, that it’s a place of strict judgements and harshness.
In terms of a person: When someone has an idea that he wants to get excited about, this knowledge must change over from being an idea to being a feeling. In this process, there must be a point where the idea stops being an idea and is not yet a feeling. At that point, it can get ‘stuck’ and not end up coming into an emotion in the heart.
For example, someone learns an idea in Chassidus about the greatness of Hashem, and contemplates on it. He thinks about how wonderful this idea is and how much it means to him. If this doesn’t produce any emotions of love or fear of Hashem, then this idea got ‘stuck’ on its way from idea to feeling.
This point is called the ‘throat,’ since it is the channel from the mind to the heart, much as the throat connects the head to the body.
Since this is a point where an idea can get ‘stuck,’ it is a harsh place, like a narrow, rocky straits where a ship could crash.
Meaning: In order to transition from intellect (head) to emotions (heart), one must pass through the constriction of the ‘throat.’
Now, having passed from the intellect and not yet becoming emotions, prior to entering the heart, that point is referred to as “Charan.”
The metaphor of ideas getting stuck before becoming emotions is a reference to the Light of Hashem in Chochma and Bina, the ‘intellect’ of Atzilus, being hidden from full revelation in Ze’eir Apin, the ‘emotions’ of Atzilus.
Until Avram was told “Lech Lecha,” Hashem’s Emotive Attributes functioned in our world without the higher revelation of Chochma and Bina. This is why there was the Flood, total destruction and anger, without being tempered. Since, when the intellect shines in the emotions, the emotions are tempered and not extreme. This is like an adult whose intellect controls his emotions, and therefore doesn’t reward beyond proportion or punish out of proportion. However, without the intellect shining in emotions, they function in extremes. This is why before the Flood people had extremely long lives and physical bounty, but were eventually completely wiped out.
