Although D'vekut has been popularized by the Ba'al Shem Tov and Chassidut, it first appears in Deuteronomy 11:22: “For if you shall diligently keep all this commandment which I command you, to do it, to love the LORD your God, to walk in all His ways, and to cleave [u-l'davkah] unto Him”-
The Ramban (Nachmanides, 13th century Kabbalist from Barcelona Spain) writes that the verse warns man not to worship God and a being beside Him; he is to worship God alone in his heart and in his actions. And it is plausible that the meaning of "cleaving" is to remember God and His love constantly, not to divert your thought from Him in all your earthly doings. Such a man may be talking to other people, but his heart is not with them since he is in the presence of God. And it is further plausible that those who have attained this rank, do, even in their earthly life, partake of the eternal life, because they have made themselves a dwelling place of the shekhinah.”
Isaac the Blind is one of the earliest mystics to make extensive use of the term, mostly in the context of achieving fullest possible communion with God by focusing on the sefirot during prayer.
The Ramak (Moses Cordovero) described devekut as the act of “clinging to God” can be used to influence the direction of divine forces in the higher worlds (Pardes Rimonim 75d)
The verb davak דבק appears frequently in Deuteronomy (4:4, 10:20, 11:22, 13:5, 30:20) in the context of cleaving to God. The Talmud asks how it is possible for man to "cleave to God" Who is a "devouring fire”.
Sometimes it means no more than "being near to" or "to cleave." However, the most usual meaning of this term, if it can be said to have a usual meaning, is "communion with God," which is achieved mainly during the time of *prayer or meditation before prayer through using the right *kavvanot, the mystical interpretations and meanings given to the words of prayer. Usually, devekut is described as the highest step on a spiritual ladder, which is reached after the believer has mastered the attitudes of fear of God, love of God, etc.
One of the most common ideas to be found in Kabalistic literature is that devekut is itself a ladder, in which a man can climb from one Sefirah to another and raise his soul from one point to another in mystical contemplation. As the various portions and words of prayer and the various deeds that the commandments require correspond to different parts and powers in the divine worlds, so does the soul rise with the works and deeds toward the Sefirah to which it is intended.
The Ba’al Shem Tov writes in Tzavat Haribash: “Whatever you see, remember the Holy One, blessed be He. Thus [when seeing an aspect of] love, remember the love of God; and with [an aspect of] fear remember the fear of God, as this is elaborated in various sources. Even when going to the privy have in mind “I am separating the bad from the good,” with the good remaining for the Divine service. This is the concept of yichudim (unifications). Likewise, when going to sleep think that your mental faculties go to the Holy One, blessed be He, and will be strengthened for the Divine service.”
A parable from Yaakov Yosef of Polnoye, Ben Porat Yosef - disciple of the Baal Shem Tov: There was once a great and wise king who magically created the illusions of walls and towers and gates. He commanded his people to come to him by way of these gates and towers, and had treasures from the royal treasury displayed at every gate. There were some who went as far as the first gate and then returned, laden with treasure. Others proceeded to gates deeper within the palace and closer to the king; but none reached the king himself. At last, the king's son made a great effort to go to his father, the king. Then he saw that there was really no barrier separating him from his father, for it was all an illusion.
It is told of how in moments of mystical rapture, Schneur Zalman of Liadi would be seen rolling on the floor, exclaiming "God, I don't want your Garden of Eden (Heavenly World), I don't want your World-to-Come (Messianic days), I just want You!”
From our 5 part course "The Essence Of Prayer"
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