My mistake. Stan Lee wrote it at the end of Amazing Fantasy #15, as Peter Parker walks off into the night, as part of the aftermath of Uncle Ben's death:
And it's still not about "hey, Spider-Man, make sure you don't kill people!"
Mr. Snyder -- can I call you Zack? -- this is still an insane take on Spider-Man.
There's no indication that Peter is seething with murderous rage. In fact, Punisher started off as a Spider-Man villain specifically for Peter to push back against the idea that criminals should just be executed. (In Spectacular Spider-Man in the 1980s, Frank was even trying to kill litterbugs.)
Peter has an incredibly strong moral compass that goes beyond "don't kill jaywalkers." It's that sense of responsibility to use his powers to help people that makes his academic life, work life and love life so complicated. His life would be easier if he stopped being Spider-Man.
The comics have explicitly argued against the idea that he, or the other traditional superheroes, think that executing criminals or even supervillains is the answer, no matter how much some people (including Frank Miller) want to see Batman kill the Joker.