Before Yaakov deceives Yitzchak into thinking he is Eisav, he tells Rivkah (Bereishit 27:12), “Ulay Yemusheini Avi VeHayiti BeEinav KiMitatei’ah, VeHeiveiti Alay Kelalah VeLo Berachah,” “Perhaps my father will feel me and I will be as a mocker in his eyes; I will therefore bring upon myself a curse rather than a blessing.” Rivkah solves Yaakov’s problem by making him wear Eisav’s clothes and by putting animal skins on his arms so that Yitzchak would think that he was Eisav. When Yaakov approaches Yitzchak and Yitzchak feels the skins he says (27:22), “HaKol Kol Yaakov VeHaYadayim Yedei Eisav,” “The voice is the voice of Yaakov, and the hands are the hands of Eisav.” Yitzchak then gives Yaakov the Bechorah, the birthright. Why was Yaakov so concerned with making his hands like those of Eisav? Shouldn’t he have worried more about his voice, which would obviously stand out more than the physical feeling of his arms?
Rashi, based on a Midrash, says that the reason that Yaakov was not concerned was that he and Eisav had identical voices. However, Yitzchak was able to recognize that he was talking to Yaakov because Yaakov spoke with a gentle voice and did so in a manner that would make a Kiddush Hashem. In addition to this answer, Ramban says that another possible explanation of why Yaakov was not worried is because he was a master at impersonating his brother. (Although Yitzchak was able to distinguish between them.)
The Sefer Ohev Yisrael has a completely different interpretation of this episode. The Pesukim state (27:6-7), “VeRivkah Amerah El Yaakov Benah Leimor, Hinei Shamati Et Avicha Medaber El Eisav Achicha Leimor, Haviah Li Tzayid VaAsei Li Matamim VeOcheilah,” “And Rivkah said to Yaakov, her son, saying, ‘Behold I heard your father telling your brother Eisav, ‘Bring me some caught food and make me delicacies to eat.’’” The Sefer Ohev Yisrael infers from here that Yitzchak expected Yaakov to speak like Eisav. He knew from the word “Leimor,” “Saying,” that Rivkah was really telling Yaakov to speak in his usual voice. This is because she overheard Yitzchak telling Eisav to speak to him in Yaakov’s tone of voice because he knew that if Yaakov would come to deceive him then he would do so in Eisav’s voice. (Yitzchak used reverse psychology to figure out what Yaakov would do.) However, since Rivkah overheard this, she told Yaakov the sign between Yitzchak and Eisav, and he therefore knew to speak in his regular tone of voice. Therefore, it appears from the Ohev Yisrael that Yitzchak’s comment of “HaKol Kol Yaakov…” was not one of confusion whether it was Yaakov or not; rather, it was a statement, “I know that since the voice is Yaakov’s, the very sign I told Eisav, and his hands also feel like Eisav’s, it must indeed be Eisav.”
The commonality between the three approaches is clear. The way Yaakov spoke distinguished him from Eisav. The Vilna Gaon says (based on a Pasuk in Mishlei 22:15) that people often make a mistake when they try to convince another person of something. He says that when they want to prove their point, they yell louder and louder. However, says the Vilna Gaon, in reality they the best way to prove a point or teach someone something is by speaking to him in a calm, gentle manner. If he yells to make his point, he will just frustrate the other person and lose any chance of convincing him.
We learn from Yaakov that the proper way to speak is with a gentle manner, in order to make a Kiddush Hashem. It is this manner of speaking which we need in our everyday interactions and conversations with others in order not to cause conflict. In addition, if we want to be an “Ohr LaGoyim”, a “Light to the Nations,” we need to be able to convince them, by making a Kiddush Hashem, the proper way to speak to other people. We should learn from Yaakov the proper way to conduct our daily interactions.
-Adapted from Imrei Baruch, a Sefer written by Rav Baruch Simon, Rosh Yeshiva at Yeshiva University.)