Answer: A group is the vessel, that part of Malchut of the world of Infinity that is disclosed to a person now as a place from which he could begin his connection with all the souls.
These are the individual souls that are closest to him. And when he reveals this connection, he will see that everything belongs to one vessel, one soul.
In the meantime, only this part is revealed to him so it would be easier for him to join it. He does not even need to connect with the entire group; he can choose a few people to whom he feels closer.
We operate under the control of informational genes, Reshimot. According to the kind of Reshimot that are revealed in us, we look at people around us and see who matches us and who does not.
We think that this is determined by the physical genes and hormones, but really, it all depends on our internal Reshimot. Even unconsciously, we attach great importance to every detail, choosing by the form, smell, and behavior of the one who matches us more or less.
It seems to us that we choose simply by external qualities, but no, our internal Reshimot speak in us. Usually, we look for “complementary,” qualities that complete us. This happens in everything, beginning from ordinary, earthly love, friends, and as well in a Kabbalistic group where deeper, richer Reshimot are revealed. However, the same principle acts everywhere.
Thus we come to the group. But when we try to connect in it, a problem arises because these Reshimot are broken. We cannot just connect under these Reshimot, completing each other. The lack of agreement between us begins to emerge. On the one hand, I like these people and understand them. On the other hand, something interferes and divides us. We need to work above these disturbances.
From the 1st part of the Daily Kabbalah Lesson 10/21/12, Writings of Rabash