אברהם הוליד את יצחק
The Torah underscores that Avraham and Yitzchak were father and son. One would think this is a confirmed verity and does not require the Torah’s reinforcement. Apparently, as Midrash Tanchuma (quoted by Rashi) posits, the leitzanei ha’dor, cynics of the generation, intimated that Sarah Imeinu actually had become pregnant during her short captivity in the home of Avimelech, so that Avraham Avinu had not fathered Yitzchak, but actually, Avimelech had fathered him. Therefore, Hashem made Yitzchak’s features so undeniably similar to Avraham’s that no one could doubt Avraham’s status. Two questions glare at us: Why were these scoffers referred to…