A theme that permeates Parshas Toldos appears in the opening passuk of the parsha. Yitzchak is identified as the son of Avraham. To emphasize this point, the Torah repeats the relationship, i.e. that Avraham was the father of Yitzchak. Rashi quotes different interpretations from the Midrash to explain the apparent redundancy of this information. Whatever the reason for this repetition, clearly the Torah is introducing the story of Yitzchak's life emphasizing that he is very much the son of Avraham. This is not merely a biological fact, rather it attests to many of the challenges Yitzchak faces throughout his lifetime; as we read Parshas Toldos about Yitzchak, it appears that we are reliving aspects of his father's life. There are many similarities between Yitzchak's family life and that of Avraham: firstly, he is not blessed with children for many years. Secondly, his son Esav brings him much pain when he chooses to marry daughters of idol worshipers, which is reminiscent of the suffering Avraham endured when Yishmael had to be banished because of his inappropriate behavior. Lastly, just as Avraham's two sons Yitzchak and Yishmael parted ways, so, too, did Yitzchak watch Yaakov and Esav separate from one another.
Additionally, Yitzchak has almost identical experiences to his father in his relationships with the neighbors that he encounters. Both leave their homes because of famine and are fearful for their lives in their new surroundings. An identical strategy of presenting their wives as their sisters is invoked by both. Although both are saved by Hashem, and Avimelech the King of Gerar treats them with respect, the people of Gerar attempt to steal and damage their property. The wells dug by Avraham and later by Yitzchak become a source of great friction as the Shepherds of Gerar are overcome by envy. The Torah highlights how Yitzchak continued in the path of his father even to the extent of calling the wells by the names given to them by Avraham. Both father and son are eventually acknowledged by Avimelech as holy men and are sought out as partners in a covenant. The similarities that occur in the lifetime of Avraham and Yitzchak are testimony that Yitzchak was the son of Avraham in the fullest sense.
As similar as Avraham and Yitzchak were, there were significant differences between them. Many of the stories the Torah tells us about Avraham highlight his acts of kindness. Welcoming guests, saving Lot from captivity, arguing on behalf of Sodom and burying Sarah all attest to Avraham being the paradigmatic man of chessed. The most significant event in Yitzchak's life is the akeida. It was this unique status of being a consecrated "sacrifice" that distinguishes Yitzchak from his father, and it was this degree of holiness which he attained that prevented him from ever leaving Eretz Yisrael, unlike his father who was permitted to travel to Mitzrayim during a time of famine.
Although Avraham is portrayed primarily as a baal chessed, clearly he is also the model of a servant of Hashem. Following the akeida, Avraham is told by Hashem that he has attained the status of being one who is "yerei elokim". He is the one who spreads the truth about Hashem to the world around him. Notwithstanding Yitzchak being known as the holy man who became the consecrated sacrifice to Hashem, he also attains greatness in his relationship with his fellow man. Avraham instills in him, "la'asos tzedakka umishpat" (Bereishis 18:19), to follow in the path of displaying charity and justice to mankind. He also calls out in the name of Hashem to others. He very much follows in the legacy of his father in caring about others. He also dedicates much effort to sharing with others the great gift of knowledge of Hashem. Both Avraham and Yitzchak are our role models in how one develops a relationship with Hashem and simultaneously looks to help others. Avodas Hashem must have both components, and since different people have different strengths and personalities, they may emphasize and excel in one of these areas more than the other.
We should never view either of these different examples of avodas Hashem as being inferior to the other. Avraham and Yitzchak were both great even if they were different, and perhaps that is why the Torah is emphasizing time and time again, "Yitchak ben Avraham." We should never think that Abraham and Yitzchak had different goals; Yitzchak lived his life continuing the legacy of his great father, faced similar challenges, and even called his wells by the names his father had given them. This symbolized that he viewed himself as the heir to the great lessons of avodas Hashem and chessed which Avraham introduced to the world.
We are all part of this dual legacy. Regardless of whether we emphasize the Avraham or the Yitzchak roll in that legacy, we are heirs to both and are all bnei Avraham v'Yitzchak who are faithfully following in their footsteps. We should use the unique combination of gifts granted to each of us and continue to walk in the path of our avos in both the bein adam lamakom and the bein adam lachaveiro aspects of avodas Hashem.
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