Tzimtzum means in Hebrew God’s contraction, withdrawal, retreat. It sometimes points to a voluntary action in which God retreats into his circumference in order to make room within himself for something else.
In the beginning God created nothing. God does not create the world directly out of himself. He first created nothingness in order to make an empty space that is marked by a radical separation between it and the God, and only into this emptiness sends the rays of emanation, which then form the bud of the future world.
The world emerges as something radically other than God, sharing only elements of the dispersed light, but absolutely discontinuous with the divine origin.
The world was created as radically other than God, but it is also charged with an obligation to put itself in order, to recreate the divine face within the immanent. So it is somehow a secret obligation of the world, a secret moral, religious duty, to pursue the Messianic path of this immanent recreation of God’s face.
— Agata Bielik-Robson
Notes from a Room 