The Torah states in (Exodus 21:12): "If one strikes a man." The language is specific — "a man." The Mekhilta immediately asks the obvious question: does this mean the law only applies when the victim is an adult male? What about a woman? What about a child?
If we read the verse in isolation, the answer seems troublingly narrow. "If one strikes a man" — a man, and only a man. The text says nothing about striking a woman, and it says nothing about striking a minor. Taken literally, the verse would create an absurd gap in the law where violence against women and children carried no capital consequence.
The Mekhilta resolves this by turning to (Leviticus 24:17): "And if a man strikes any soul of a man." The phrase "any soul of a man" is broader than "a man." It encompasses every human being — man, woman, and child. The Leviticus verse expands the Exodus verse, clarifying that the law against fatal assault applies regardless of the victim's sex or age.
This is a textbook example of how the rabbis used cross-referencing to prevent unjust readings of individual verses. No single verse in the Torah was meant to stand alone. Each law exists within a web of related passages that qualify, expand, and complete one another. The narrow language of Exodus is not a limitation — it is an invitation to look elsewhere in the Torah for the full picture.
The practical result is a legal system that protects every human life equally. Whether the victim is a man, a woman, or a child, the person who struck the fatal blow faces the same consequence. The Torah's universal protection is established not in one verse, but in the conversation between two.