Chazal (Bereishis Rabbah 23:1) quote from Sefer Tehillim (37:18), Yodea Hashem yemei temimim… “Hashem knows the days of the perfect.” K’shem she’heim temimim, kach shenosam temimim, “Just as the righteous are perfect, so are their years perfect.” They say this concerning Sarah Imeinu whose life was one long series of perfection. In an alternative exposition, Rabbi Yochanan says, “Sarah was perfect in her deeds,” k’hada eglesa temimsa, “like an unassuming calf.” Rabbi Yochanan equates temimus, perfection/wholeness, with the trait of obedience and unassuming (no questions asked – no answers expected). She followed instructions i.e. tzivui, command of Hashem, faithfully. As a calf follows its master wherever he leads it, so, too, did Sarah follow Avraham Avinu, his guidance and direction.
The Bais HaLevi expounds on the concept of temimus, following faithfully. One who is faithful and obedient does not question, “Why?” This form of faithfulness is characteristic of the obedience of an animal. The average human being who follows a command does so because he has mulled it over and decided that it is beneficial for him to follow instructions. Thus, he is actually serving himself, not his fellow. In contrast, an animal has no free will and no real cognitive ability. Thus, it follows its master’s wishes obediently. The highest service we can perform to Hashem is to carry out His command without questioning, as an animal obeys its master. In the process of Torah study, we are permitted to delve into the rationale behind a mitzvah, but, in no way do we consider the logic at which we arrive to be the actual reason. We serve at Hashem’s will, without question. This is why Chazal compare Sarah Imeinu’s temimus to that of an unassuming calf.
The Shem MiShmuel cites his father, the Avnei Nezer, who explains temimus as unwavering commitment regardless of the circumstances in which one finds himself. Yetzivius, stability, and ikvius, consistency, are two terms which describe the tamim. Under all circumstances, the adam ha’shaleim, complete, perfect man, the tamim, will maintain his total conviction in Hashem.
Horav Tzadok HaKohen, zl, (Pri Tzaddik Chayei Sarah), quotes his saintly Rebbe, the Ishbitzer, Horav Mordechai Yosef Leiner, zl (Mei Ha’Shi’loach) who interprets eglah (which we have translated as calf) to be derived from the word agal, circle. A circle has no beginning and no end; everything is equal. Equanimity best describes the attitude of one who is compared to eglah. [While a circle is often associated with notions of perfection due its continuous and infinite nature, it is important to note that perfection can be subjective and interpreted differently by individuals.] The idea of a circle having no beginning and no end symbolizes its unbroken and self-contained form, which can be seen as representing perfection, and perfect harmony.
With this in mind, we have a deeper perception of Chazal’s comparing Sarah to an eglah temimah. Rather than addressing obedience and faithfulness of an animal, we are talking about the perfection of a human being who, under circumstances throughout the peaks and valleys of her life, remained the same with complete equanimity, just like an agal, circle.