In this week’s parshah, Yosef reveals himself to his brothers. At first they are in shock, and so, in an effort to prove his identity to them, Yosef showed his brothers that he had a bris milah (Rashi, Bereishis 45:12).
Mefarshim are bothered by an obvious question. Rashi (Bereishis 41:55) writes that Yosef commanded every male in Egypt to have a circumcision when they came to him for food and could not afford it. Surely this made headlines around the civilized world. How, then, did Yosef having a bris milah serve as proof to his brother that he was Jewish?
Additionally, Bnei Yishmael and Bnei Keturah (Sanhedrin 59b) are obligated to have circumcisions as well. Of what value, therefore, was Yosef’s demonstration that he had a bris, asks the Re’eim (quoted by the Mishneh Lemelech)?
The Mishnah Lemelech points out that Rashi (but not the Rambam) maintains that only the actual sons of Keturah had to be circumcised, not their descendants. According to Rashi, then, we have a partial answer.
The Chizkuni writes that Bnei Yishmael only perform milah at the age of 13 and therefore the priya (ripping of the foreskin) is not as recognizable on them. Yet, our question remains since Bnei Keturah are obligated to have a bris at eight days old (according to the Rambam) and Yosef could have been a descendant of Keturah. Perhaps he was even born circumcised (as Bilaam was – see Avos D’Rabi Nasson 2:5).
Some have pointed out that the Gemara says that priyah was not an obligation until Maamad Har Sinai. Before that point, the only ones who performed it were Bnei Avraham, Yitzchak, v’Yaakov. By showing his brothers that his milah had priyah, Yosef proved that he was a member of the family.
I would like to suggest a simple answer to our questions. But first, I want to pose another one: Why did Yosef require every male in Egypt to undergo a circumcision? Rashi writes that he did so because Yosef acquired all the Egyptians as slaves and halacha requires that one perform milah on all one’s slaves, even non-Jewish ones. Therefore, by showing his brothers that he was circumcised, Yosef was proving his Jewishness. For who else would have required his “slaves” to become circumcised other than a Jew?
Finally, perhaps Yosef merely used his circumcision as one proof among several. It was not an ironclad proof, but Yosef used it as a means to slowly convince his brothers that he was whom he claimed to be. One thing they knew for sure: if he didn’t have a bris, he couldn’t be their brother. So he showed them that he was circumcised. It was not the only thing Yosef did to prove his identity; rather, it was one of several.