3.1 - Shaar HaYichud: The Gate of Unity

Sources refer to Rabbi Bachaye ibn Pakuda's Chovos HaLevavos (Duties of the Heart)



The most basic, fundamental principle in Judaism is the acknowledgment of God’s unity. This idea is what separates believers from non-believers; it is a non-negotiable concept for a practitioner of Judaism. This is why the first words spoken to the Jews at Sinai were, “I am Hashem your God…” (Exodus 20:2). This idea is later reiterated in the Shema, “Listen, Israel: Hashem is our God; Hashem is One” (Deuteronomy 6:4).

Reciting the Shema covers ten subjects, corresponding to the Ten Commandments that were communicated at Sinai. It starts with belief in God. “Shema” means not to hear with one’s ears but to understand and internalize the ideas that (1) God exists, (2) He is our God, and (3) He is One. (4) We are then told to love God with our hearts, souls and might (Deut. 6:5). (5) We continue with the obligation to fulfill the duties of the heart (6:6), meaning that one should always be permeated with these ideas. We are then told to fulfill physical obligations of the body and mind, such as (6) teaching Torah to our children and (7) speaking of it at all times (6:7). Doing so ensures that a person’s thoughts are never bereft of God. Finally, we are told to fulfill actions that are purely physical, like putting on tefillin (8) on the arm and (9) on the head, and (10) hanging a mezuzah (6:8-9). These things serve to remind us of God so that we keep Him in mind at all times. You will note that the first five obligations are spiritual in nature, while the latter five are more physical.

Acknowledging God’s Unity (Chapter 1)

What does it mean for a person to completely acknowledge God’s unity? One must investigate the matter until his heart, mind and tongue are all in agreement that God exists and that He is One. Some people only acknowledge God’s unity with their mouths, repeating what they have heard but not truly comprehending it. Others understand it after some work but they imagine God’s unity as comparable to the unity of physical things. They attribute a temporal existence to God because they do not really grasp His nature. The proper way is research the matter until one achieves a true understanding of God’s absolute unity.

Understanding God’s Unity (Chapter 2)

The expression “unity” is used by many people who don’t really understand it. They think that just saying it means they’re acknowledging God’s unity and that that is sufficient. It isn’t sufficient because in their hearts they’re still picturing God as similar to other beings, or they attribute traits to Him that really don’t apply. Because of this, there are four levels of acknowledging God’s unity, which depend on the different levels of insight and understanding one might achieve.

The first level is a simple verbal declaration. This is appropriate for children but we also find it among people who have not attained understanding.

The second level is in the heart based on a received tradition. Such a person has been told by trusted figures that God is One and he believes it, even if he doesn’t really understand what that means. The problem is, what if the one who told him also doesn’t understand it and is just parroting what he has been told? It’s possible to have a string of people, all of whom accept what they have been told but none of whom actually understands it. All it would take for such a chain of people to go awry is for one of them to make an error. This is why the Sages impressed upon us to be diligent in Torah study and to know what to answer a heretic (Avos 2:14).

The third level is being able to support God’s unity through intellectual arguments even if he doesn’t really understand the concept of absolute unity. This is like a person who knows the general directions to his destination but who comes to a fork in the road and doesn’t know which path to take. He can exert a lot of effort and never reach his goal. (This metaphor is based on Ecclesiastes 10:15, “The labor of fools wearies them all since they don’t know how to get to the city.”)

The fourth level is when one analyzes the matter of God’s unity to the extent that he reaches a correct understanding of what it means for God to be One. This is what the Torah means when it exhorts us to “Know this day and place within your heart that Hashem is God in Heaven above and upon the earth below; there is no other” (Deuteronomy 4:39).

The Obligation to Investigate (Chapter 3)

If a person has the intellectual capacity to investigate the unity of God, then he also has the obligation to do so. The Torah states this obligation in the aforementioned Deuteronomy 4:39, “Know this day and place within your heart, that Hashem is God in Heaven above….” Similarly, King David told us to “Know that Hashem is God” (Psalms 100:3). God also said, “If a person must take pride in something, let it be in that He understands and knows Me” (Jeremiah 9:23). We know this obligation from Biblical verses, from an oral tradition, and from logic. If a person has the ability but neglects this duty, he fails himself, like a sick person who knows how to cure his own illness but just can’t be bothered to do so.

Establishing God’s Existence (Chapter 4)

Before undertaking a search to understand something, one must first ascertain that it exists. Once that has been established, one can start inquiring into the object’s nature. When it comes to God, a person must first satisfy himself that God exists. After that, he can delve into the nature of God’s unity and what exactly that means. Doing so fulfills the exhortation of the Shema, to strive to understand that God exists and that He is One.

Therefore, the process is (1) to establish that the world has a Creator, (2) to determine that He is One, and (3) to understand what absolute unity is and what attributes that entails. With God’s help, one may achieve a complete acknowledgment of His unity.

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