Answer: It is a connection that is created above the feeling of separation, since we achieve it by ourselves and this achievement is based on the contrast between two opposite states. Above the resistance between them, we discover our achievement.
It is like a resistor in an electric circuit that resists the connection between two points by creating a resistance between them. However, if we connect this network to two poles, we create a potential difference, and then by this resistance we can clarify what the difference is: By clarifying the gap and the relations between them we can understand what is on one pole and what is on the other. All this is clarified by the resistor, by the resisting force.
The system of life is built on this basis—on the connection of opposite particles. These particles connect into atoms and the atoms into molecules and everything connects on the basis of opposites, a plus with a minus.
Different materials are created thanks to the different connections between the positive and negative particles. Such internal opposite qualities are typical of every material, of all the elements on the periodic table. Later this connection between the plus and the minus becomes increasingly varied and complex. Different qualities appear in it, which turn these creations into living cells.
It isn’t a static system anymore in which the plus and the minus are connected in a stable relationship to one another, but a system in which this relationship begins to change and thus the element of life is created.
The lower can already exist not simply adhering to the upper the way it was in the world of Ein Sof (Infinity), or separated from Him, like after the descent of the worlds to this world, but also in starting to perform independent movements with regard to the upper. This is already a change from the level of the still level of nature into the level of the vegetative and then into the animate level and finally into the level of the speaking. This is how the ascent up the levels occurs.
This is how life is created in this world and this is also what happens in the spiritual world as a person advances and annuls the partition that separates him from the Creator.
From the 1st part of the Daily Kabbalah Lesson 9/13/12, “A Speech for the Completion of The Zohar”