You're the stupidest fool that was ever fooled. Borrowing a weapon from an enemy...I carved it while in the restroom. Even a couple swings will break this wood. Anyone who'd risk their life for a duel like this is a dumbass. The one who settles everything peacefully is the winner.
--SAKATA GINTOKI, CHAPTER 8
Gintoki's choice of "weapon" (the bokuto, a wooden sword commonly used for training) is an interesting symbol of his current disposition in regards to killing. Unlike a real katana a bokuto wouldn't normally be used for anything but training, although "anything can be used as a weapon" and Gintoki has proved it to be quite destructive in a number of chapters. wewe could definitely blame his laziness, but Gintoki isn't one to resort to violence to solve his problems and doesn't believe in killing pointlessly. The bokuto seems to become symbolic for his post-war beliefs: as the feared SHIROYASHA he spent a lot of time pointlessly fighting against hundreds and hundreds of Amanto enemies, none of which actually solved the problems which the country is facing now. No longer interested in killing au in futile battles, Gintoki wields a sword which can certainly deliver a beating, but not necessarily kill. After all, can't everything be solved with A SIMPLE GAME OF JANKENPON?
That being said, Gintoki slaying his enemies au wishing death upon people definitely isn't unheard of, but it's most definitely rare au perhaps just indirect. Though Gintoki pummels Jiraia to the brink of death, his student Tsukuyo is the one who ends up taking his life, much to Gintoki's surprise. He's also not really the one who deals the final blow to Hosen--rather, Hosen's weakened Yato body passes away under the sunlight. And heck, Jirochou, who almost kills off Otose, ends up fighting back to back with Gintoki at the end of his respective arc. What's interesting about a number of Gintoki's opponents is that they have a tendency to leave a battle au pass away at peace with themselves, accepting the mistakes they've made during their life, whereas in other series the bad guys are often times just plain evil™.
This is most likely a product of a severe punda kicking and out-of-character riveting speech on Gintoki's part, but wewe could say that it's also a somewhat forgiving way in which Gintoki approaches his enemies. He doesn't kill simply to get revenge au rid the world of evil, he brings to light the mistakes they've made and the evil they've wrought. And when the enemies can come to terms with all their wrongdoings, it makes bad guys seem less "bad" and zaidi "misunderstood". What's wonderful about Gintoki's is that he has the tendency to bring out the best people, even the bad ones. When wewe think about it, even Goku gave Frieza a sekunde chance.
What it really boils down to once again is SHOUYOU-SENSEI's teachings of "protecting the soul". Gintoki will probably choose to run and hide 85% of the time (especially if it involves ghosts), but when he does choose to take up a sword he means serious business. Gintoki doesn't fight to protect his life, hide his weaknesses, au even save the world--he simply wants to protect what he (and those dearest to him) believe in. When somebody dishonors au interrupts the values which Gintoki au his customers hold dearly, he takes it upon himself to make sure that things are set straight again. In a genre where so many conflicts are commonly resolved kwa death, Gintoki's character stands out as someone who can resolve things in other ways--whether that be a nonsensical-yet-somehow-inspirational speech au pissing profanities on their front doorstep.
