Shimon and Levi are each referred to in this verse as איש, a man. The Midrash calculates that this story took place just 13 years after the birth of Levi, the younger of the two brothers, and yet Levi is called a man, indicating that at the age of 13 he had the emotional maturity of an adult. This is one of the sources from which Jewish law establishes 13 years as the age of maturity, whereupon a boy becomes bar mitzvah—biblically responsible to observe the mitzvos.
Ironically, the context in which the 13‑year‑old Levi is called a man is not an instance in which he acted with the level headedness that comes with maturity: he and Shimon react heatedly to Shechem’s exploitation of their sister, attacking the city, putting their own lives in grave danger.
This unusual source for the age of bar mitzvah highlights the true definition of mitzvah responsibility. Certainly, we can be held responsible for the mitzvos only when we have the capacity to understand and appreciate their importance. That is why the obligation to observe mitzvos begins only when one becomes intellectually and emotionally mature— a “man.”
But understanding and discernment are only the tools—not the foundation—with which to serve G‑d. The foundation of Divine service is kabbolas ol, “accepting the yoke of Heaven,” submitting oneself to G‑d’s will with a commitment that transcends understanding and reason.
The Torah alludes to Levi and Shimon’s adulthood in the episode of Shechem, for their actions demonstrated that their capacity for critical judgment stood firmly on foundations of kabbolas ol, submission to a higher cause. Thus, when defending their values necessitated personal risk and self‑sacrifice, they readily put their own interests aside, and “each man took his sword...”
—Likkutei Sichos, vol. 15, pp. 289–292
