Differences in form act spiritually much as the axe acts physically to separate things. The distance [between the two spiritual things] will be proportional to the difference in form. Understand, as discussed, that souls are imbued with a desire to receive pleasure, which, as we demonstrated, does not exist at all within the Creator. Heaven forfend! From whom could God receive?! This change in form that the souls acquire serves to separate them from God’s essence, much as the axe separates a stone from the mountain. This change in form detaches the souls from God, and they become creatures separate from Him. Still, anything that the souls acquire from God’s light flows from a pre-existing reality, from God’s essence.
Spiritual Separation Works Like an Axe on Stone
Baal HaSulam's Introduction to Zohar 9:1