Da'as Tevunos - Section 74

Said the Intellect - This is the generalization, the body - its creation is dark and it has deficiencies, and it has refinement by the soul. The soul - its source is great, however it diminishes itself when it comes into the body, in order not to refine it excessively in one moment and not to change it from its manner of creation; rather little by little it acts upon it as it needs through good acts. And afterwards is elevated according to its actions, and its strength is made greater according to its elevation, and the refinement is multiplied in the body according to the greatness of its strength, until it become appropriate to stand with it together to look upon the beauty of haShem and to visit his sanctuary, for ever and ever.