

ספירת היסוד is the sixth and final of the six מידות, and the ninth of the עשר ספירות.יסוד (Yesod) is the attribute of desire and ability to connect with and influence others, also called צדיק (Tzaddik) and טוב (Tov). [1] Its role is to channel and unify all the preceding מידות, preparing them for actualization in ספירת המלכות.
Etymology
The name יסוד means “foundation.” The word טוב (Tov) has a numerical value of 17, corresponding to the letters א"ה ו"ה (Ah-Heh Vav-Heh), which hint at “the heavens and the earth,” reflecting יסוד's role in uniting them. [2] Additionally, יסוד is called כל (Kol), which has a numerical value of 80, the same as the numerical value of יסוד itself. [3]
Definition
יסוד is the ninth of the seven lower ספירות, corresponding to the emotions (מדות). [4] It is part of the middle line of the ספירות of Yosher (Upright), along with דעת and תפארת, and its position is after them. [5]
It is the capability of uniting the giver with the recipient, bringing influence out from one to the other. This is why it is called כל, based on the verse “for all (כל) that is in the heavens and on earth is yours,” which the Targum Aramaic translates as “He unites the heavens and the earth.” [6]
יסוד also acts as a mediator, combining the seemingly opposite gut emotions of נצח (Conquest) and הוד (Majesty). [7] It represents connection on the gut level, as it relates to action.
All influence from יעקב (Yaakov), representing the emotions (מדות), gathers in יסוד before coming out into revelation. [8] יסוד's ability to bring this influence down to the recipients is because it is rooted even higher than the intellect (שכל) and influence itself. It is specifically one who understands a concept at its very essence and source who will be capable of bringing it down to the comprehension of a child. [9]
יסוד is a vessel for the gut emotions (נצח, הוד, יסוד) of the emotions (מדות). [10]
From the perspective of the recipient, before a person can speak or act (מלכות), there must be a sublimation to that which is above it, like a point under יסוד. The beginning of action (מלכות) is its sublimation to the desire, intellect, and emotions. [11]
Teachings of the Rebbeim
The Mitteler Rebbe, in Shaar HaYichud,explains that יסוד is part of the middle line, which connects the two lines to its right and left. [12] He describes יסוד as the capability of uniting the giver with the recipient, as seen in the verse “for all is in the heavens and the earth,” which translates as “He unites the heavens and the earth.” [13] He states that all influence from the emotions gathers in יסוד before revelation. [14] Furthermore, he explains that יסוד's ability to bring influence down comes from being rooted even higher than intellect. [15]
References
- ↑ The Knowledge of Hashem, 1:27, 1:73
- ↑ The Knowledge of Hashem, 1:73; Shaar HaYichud (The Gate of Unity), Ch. 36
- ↑ The Knowledge of Hashem, 1:109
- ↑ The Knowledge of Hashem, 1:27
- ↑ The Knowledge of Hashem, 1:72
- ↑ The Knowledge of Hashem, 1:73; The Knowledge of Hashem, 1:109; Shaar HaYichud (The Gate of Unity), Ch. 36
- ↑ The Knowledge of Hashem, 1:72
- ↑ The Knowledge of Hashem, 1:73; Shaar HaYichud (The Gate of Unity), Ch. 36
- ↑ The Knowledge of Hashem, 1:73
- ↑ The Knowledge of Hashem, 1:55
- ↑ The Knowledge of Hashem, 1:104; The Knowledge of Hashem, 1:108
- ↑ Shaar HaYichud (The Gate of Unity), Ch. 36
- ↑ Shaar HaYichud (The Gate of Unity), Ch. 36
- ↑ Shaar HaYichud (The Gate of Unity), Ch. 36
- ↑ Shaar HaYichud (The Gate of Unity), Ch. 36