Action (Levush)
"Action" is an innate tool the soul uses to express his faculties. The tools used to consciously tap into and express the Soul and its faculties are referenced to in Chassidic terminology as a garments. This is the lowest of the three garments (the first two are thought and speech. As opposed to the other garments where there is an apparent connection between the soul's faculties and the garment [i.e. a thought must be processed by the soul's intellectual powers or emotions; speech, likewise, must reflect on a thought or feeling], this garment is "disconnected" from its source [i.e. one can do a meaningless action or an action that opposes his thoughts and feelings].
Though this garment is the lowest and can be missing the vitality found in the other garments, using this garment constitutes the essence of divine service, as stated in the Mishnah in Avot: "Study is not the main thing, but rather action."[1]. Specifically through action we bring about and reveal holiness in the world.[2]
The Virtue of the Power of Action
Although from a human perspective there is virtue in service through thought, wisdom, understanding, and knowledge, from the perspective of revealing G-d's sovereignty in the world, there is a particular advantage specifically in action that recognizes and reveals His sovereignty in the world.
Action Is Supreme
The Zohar teaches that "action reigns supreme." This means that although the garment of action is the lowest of the three garments of the soul and represents the end and culmination of all powers, it specifically contains the virtue of "their end is wedged in their beginning." Through action, the essence of the soul is drawn forth, and through it, the essential divine light is extended.[3]