The study and practice of Kabbalah have a primary goal: to help guide the soul back to the Godhead. For each Sefirah ("emanation") there is a corresponding ethical attribute in human behavior. The person who devotes himself to perfecting this attribute is integrated into the mystic world of the Sefirot. Attaining this higher level is known as the process of devekut, mystical cleaving to God.

To be sure, there are different levels of devekut to be attained. How close one can come to God is seen through the image of ascending the rungs of a ladder. This raised a serious debate among the kabbalists. Which was a more worthy attribute--the fear of God or the love of God? Many kabbalists felt that worship of God in "pure, sublime fear" represented a higher rung of attainment than worship of Him in love. Isaac the Blind asserted: "The principal task of the mystics is expressed in the commandment, ‘And ye shall cleave unto Him’ (Deut. 13:5). And this is a central principle of the Torah, and of prayer, and of reciting the blessings, to harmonize one’s thought with one’s faith as though it cleaved to the worlds above, to cojoin God in His letters, and to link the ten Sefirot in Him as a flame is joined to a coal."

Nachmanides defined devekut as the state of mind in which "you constantly remember God and His love, nor do you remove your thought from Him." Thus a true "mystic" is always focused upon his relationship with God, even when he is speaking with someone else. This divinely directed person becomes eligible to receive the divine spirit. Meir ibn Gabbai wrote: "When the spirit returns to the Source, it cleaves to the celestial light from which it derives, and the two become one."

Devekut combines a sense of beatitude and intimate union, although it does not entirely eliminate the distance between the creature and its Creator. Even the most extreme kabbalists were careful to avoid a doctrine that promised complete unification of the soul and God. In the thought of Isaac of Acre, the concept of devekut takes on a contemplative, ecstatic character.

Was there a practical method to achieve this mystical "cleaving"? Did the performance of mitzvot, "commandments," provide a direct path to the Godhead? This was a route to completion, albeit a circuitous one. In the realm of Kabbalah, prayer serves as the ultimate vehicle for mystical ascent. The greatest kabbalists were all great masters of kavvanah, prayer of "intent."