As a reward for our patriarch Avraham having said, ‘I am but dust and ashes,’ his descendants merited to receive two commandments: the ashes of the red heifer, and the dust that is mixed with water for a sotah.
These two mitzvos correspond to more than just the metaphor of “dust and ashes” that Avraham used to describe his humble existence. The red heifer and the sotah water reflect the essence of Avraham’s conduct, which he expressed with the words “I am but dust and ashes.”
With these words Avraham effectively described the motivation behind his life of selflessness: his utter humility. Avraham was so insignificant in his own eyes that he felt certain that everyone else was surely entitled, equally or more, to the goodness with which he had been blessed. In fact, Avraham did not hesitate to help another person even when it might have caused him personal harm or loss. Thus, saving his nephew from captivity warranted risking his own life in battle; tending to the physical needs of travelers whom he imagined to be pagan nomads justified forfeiting his time with the Divine Presence.
As a reward, Avraham’s descendants, the Jewish people, were given two mitzvos that exemplify this attribute of selflessness—the ashes of the parah adumah, the red heifer, used to purify those who contract impurity from a corpse; and the sotah water, used to prove the innocence of a suspected adulteress.
By Divine decree, all who were involved in preparing the ashes of the parah adumah contracted a degree of impurity themselves. Similarly, the preparation of the sotah water required erasing (into water) the ink of several verses from the Torah, including G‑d’s holy name. A Jew’s ability to allow himself to become impure in order to spare someone else the inconvenience of impurity, or to actively desecrate G‑d’s holy name in order to save someone else’s marriage, is truly the legacy of Avraham, who put all others before himself, viewing himself as nothing “but dust and ashes.”
—Likkutei Sichos, vol. 25, pp. 79–83
