Answer: A Tzimtzum (restriction) is the first condition that differentiates this world from the upper world and differentiates an intention in order to receive and an intention in order to bestow.
In this way I go out from a perception of the physical reality I am now, like all of humanity, and break through the Machsom (barrier) that is placed before me in order to begin to feel and live on its other side.
The Tzimtzum determines on which side of the border of the spiritual world I am found. A Machsom is a potential obstacle, a potential level, above which it’s necessary to leap in order to enter into the new dimension, the new world. And it’s possible to do this through a Tzimtzum of desires. A Tzimtzum requires gradual preparation and a great effort with a great need to move towards the perception of a new life, where I only want to be directed from myself outward, beyond my nature.
From the 1st part of the Daily Kabbalah Lesson 4/29/14, Shamati #141