[2] An atheist merchant/trader, John Garth, is the only human on an alien planet where the native Weskers, intelligent but painstakingly literal-minded amphibians, live in what seem to be utopian conditions.
Once at the church, Garth, who had previously made preparations to leave the planet, sees the Bible open to an illustration and orders the missionary to come with him.
Not understanding what's wrong, Father Mark refuses; but before Garth can explain, several natives seize the priest and drag him to a hill upon which is planted a cross.
Three days later, after Father Mark has been buried and the hypothesis disproved, Itin asks Garth what went wrong, and arrives at a simple truth: that the Weskers are now murderers.
[3] Paul Cook describes "The Streets of Ashkelon" as "bitterly ironic" and "one of the saddest science fiction stories ever written", saying that it "gives credence (of a kind) to the spirit of the Prime Directive".