Samson killed the lion with his bare hands. It was a violation of the Nazirite law to touch a dead corpse (Numbers 6:6–8). It was necessary for Samson to touch and kill the lion in self-defense, but having done so, he should have rededicated himself in an eight-day ritual that involved shaving his head, offering sin, burnt, and guilt offerings (Numbers 6:9–12). But he does not. At least, the text makes no mention of it.
6 Then the Spirit of the LORD rushed upon him, and although he had nothing in his hand, he tore the lion in pieces as one tears a young goat. But he did not tell his father or his mother what he had done.