"Shall Not Perish" was William Faulkner's sequel to "Two Soldiers," which detailed a young boy's love for his brother who enlists to fight in World War II. In "Shall," the family receives word that the brother has died, and they examine and accept their grief in different ways.
During the story, Mother and the narrating young boy visit Major de Spain, who has also lost his son in the war. He is sitting at a table draped with the Confederate flag, where his own father had served, and a pistol sitting in the middle of the table. He berates Mother for not staying at home to pray and love her remaining son, something he cannot do because he only had one. She goes straight to the table and grabs the gun:
"I can tell you something simpler than that," she said. "Weep." Then she reached the table. But it was only her body that stopped, her hand going out so smooth and quick that his hand only caught her wrist, the two hands locked together on the big blue pistol.
"When? When all the young men are dead? What will there be left then worth the saving?"
"I know," Mother said. "I know. Our Pete was too young too to have to die." Then I realized that their hands were no longer locked, that he was erect again and that the pistol was hanging slack in Mother's hand against her side....
(Faulkner, "Shall Not Perish," archive.org)
The implication, never spelled out, is that Major de Spain was about to commit suicide over the death of his son. While Mother is no less grief-stricken about her own loss, she is more pragmatic; she has a family to feed and duties to perform, while de Spain is wealthy and has no other family. If she allows her grief to control her, others will suffer; she does not want to see de Spain die in a useless gesture, and so she takes the gun, holding it from him until she can counsel him into a more accepting state.