Vision and Revelation
The Torah portion Vayeira, the Hebrew word for revelation, begins by stating that “G‑d revealed Himself to him Avraham in the Plains of Mamrei…. The Zohar note that, prior to Avraham’s circumcision, he could only encounter G‑d in a “bamachazeh” — the Aramaic word for vision. After his circumcision, he attained such a lofty state that G‑d clearly revealed Himself to him — vayeira.
Clearly, it was the act of circumcision that brought about this radical change in Avraham, so that he became able to see G‑d Himself. What was it about circumcision that brought about this transformation?
The difference in the spiritual quality of Avraham before and after his circumcision will be understood by considering the explanation provided by Chassidus regarding the difference between Hebrew and other languages, which is likened to the difference between stones and bricks.
The basic difference between these two materials lies in the fact that stones are a heavenly creation while bricks are created by man. The same difference exists in languages, and in the letters and words from whence language is “built.”
The Hebrew letters, the letters of the Torah, are heavenly — likened to stones, for the Torah itself is of Divine origin. However, the letters and words of other languages are compared to bricks, for all other languages are entirely artificial — people got together and agreed that particular words would convey certain meanings.
The difference in Avraham before and after his circumcision will be understood accordingly. Until G‑d commanded Avraham to perform the mitzvah of circumcision, all of Avraham’s service was entirely self-motivated, without command — and thus empowerment — from Above. As such, his service was necessarily limited, for a created being can only reach so high
Once G‑d commanded Avraham to circumcise himself, he was empowered from Above with the ability to unite with the Almighty through the performance of a boundless G‑dly commandment, thereby enabling him to reach infinitely higher.
Moreover, performing the mitzvah of circumcision also had the effect of wholly nullifying Avraham and uniting him with G‑d, for the commandment of circumcision possesses a quality possessed by no other mitzvah — it is performed upon the person’s body itself, so that the physical body is aware of its nullification and unificationwith G‑d.
Thus, the level of Avraham’s service prior to the mitzvah of circumcision was similar to “bricks;” it was man-made, and thus necessarily limited. Only after he acted in response to the commandment to circumcise himself did his level of service rise to that of “stones” — accomplished through and empowered by the limitless force of the Divine.
This is also why Avraham’s level prior to circumcision was only that of “bamachazeh,” for it was similar to man-made bricks. With circumcision, however, Avraham attained Vayeira, the Hebrew word for revelation, similar to “stones” that derive from heaven.
Before Avraham was circumcised, i.e., before he reached total unity with G‑dliness, he was only able to view G‑d through the veil of a vision, while afterwards, he was able to view a clear and lucid revelation of Essence.
As “the deeds of our forefathers serve as a lesson to their descendants", there is a lesson here for us all:
Just as Avraham failed to reach the highest levels until he performed the mitzvah of circumcision, so too are we to know that we must never be satisfied with our current level of spiritual service, but must always attempt to reach higher; even when one apprehends G‑dliness, it may be merely on the level of a “vision.”
On the other hand, we are assured that when a person serves as best he can with his own power, he will ultimately receive the most lofty degrees of revelation — up to and including the supreme revelation of vayeira.
Chassidic Dimension - Volume 3: Vayeira -Based on Likkutei Sichos, Vol. X, pp. 50-54