|Rav Arush at a Brit on the 7th day of Hannukah|
Yosef then said to his brothers, "Please come closer to me," and they drew closer. He then said, "I am Yosef your brother whom you sold to Mitzrayim."
Rashi comments on this verse that Yosef saw that his brothers were frightened (after he revealed himself to them), so he brought them closer and showed them that he was circumcised.
In the sefer Zohar Torah written by Rav Yudel Rosenberg (which is a collection of sayings from the Zohar on each parasha) it says:
Why did Yosef call his brothers closer to him, were they not already standing close? Rather, when he told them that he was Yosef, they became shocked and bewildered because they saw that he possessed the upper Malchut (rulership). Yosef then said to them, I achieved this level of Malchut because of this... he then told them to come closer and he showed them his brit milah. He said it was this that caused me to get to this level of Malchut, because I guarded my brit. From here we learn that one who guards his brit will ultimately receive Malchut. From where do we know this, from Boaz, who instructed Ruth to sleep in his bed until the morning (Ruth 3:13). He overcame his desire and swore an oath to her and by passing this test in which he guarded his brit, he merited to have rulers come from his seed, including the Melech Mashiach who is called in the name of Hashem.
Rav Shalom Arush mentioned in several past shiurim that the only way to achieve personal holiness is by guarding the eyes. The eyes are the seed of all of our desires, as our Rabbis teach us, "The eyes see, ther heart desires, and the body carries out the deed." So therefore, one must begin by praying to Hashem every single day to be worthy of guarding his eyes. The Rav also mentioned that it is not only to avoid sin and improper desires that we guard our eyes; but it is also the only way to see Hashem in this world and how He is constantly communicating with us and trying to draw us closer. This world is actually created to conceal Hashem, therefore, if we look at it, we will certainly get confused and misled. Only by closing our eyes to the physical world, do we merit true vision which is the ability to see Hashem. This is the hidden light that has been stored away for the Tzaddikim. And who is called a Tzaddik? One who guards his eyes and brit.
May we all be worthy to experience the light of holiness and may our eyes merit to see the coming of Moshiach and the Third Temple speedily and in our days, amen.