Simeon's name comes from the same wound as his older brother's. Leah names her second son "hearing" — "because the LORD hath heard that I was hated, he hath therefore given me this son also" (Genesis 29:33). Notice the word she chooses: not "loved," not "seen," but "hated." She's naming her own reality without softening it, and it's worth pausing on that honesty before moving to what her son becomes.
What Simeon becomes is trouble. After their sister Dinah is raped by Shechem, Simeon and his brother Levi respond not with restraint but with a massacre — they deceive an entire city into circumcising themselves, and on the third day, while the men are still in pain, "took each man his sword, and came upon the city boldly, and slew all the males" (Genesis 34:25). Jacob rebukes them immediately, worried about the consequences for the whole family — but notice what he doesn't rebuke: not the violence itself, at least not in the moment, only the danger it's put them in. It's only later, on his deathbed, that Jacob finally names the act for what it was.
That deathbed blessing is really a sentence being carried out. "Simeon and Levi are brethren; instruments of cruelty are in their habitations. O my soul, come not thou into their secret... for in their anger they slew a man, and in their selfwill they digged down a wall. Cursed be their anger, for it was fierce; and their wrath, for it was cruel: I will divide them in Jacob, and scatter them in Israel" (Genesis 49:5–7). Watch that last line especially, because it's not just poetry — it's prophecy that gets literally fulfilled centuries later. When the tribal territories are finally allotted in Joshua, Simeon receives no independent land of its own at all; its cities are carved out from inside Judah's territory instead (Joshua 19:1–9), and the tribe effectively disappears into its neighbor over the following generations. The scattering Jacob spoke over his son becomes, quite literally, Simeon's whole subsequent history.
There's one earlier scene worth returning to before you close the book on him, though — a moment of real vulnerability rather than violence. When Joseph, unrecognized, tests his brothers in Egypt, it's Simeon he singles out and binds before their eyes, holding him hostage until the others return with Benjamin (Genesis 42:24). The man who once dealt out violence without restraint spends what may be months in an Egyptian prison, entirely at the mercy of a brother he doesn't yet know he's talking to. Whatever satisfaction you might feel at seeing the tables turned, notice that the text doesn't linger on it as justice served — it simply reports it, and moves the larger story of reconciliation forward regardless.
Simeon's whole arc is a hard but honest lesson about anger untethered from restraint: what you do in your "selfwill," as Jacob calls it, doesn't stay contained to the moment you did it. It follows the family, and eventually it follows the name itself, until there's barely a distinct tribe left to carry it.