Catherine rejects organized faith, and yet (unlike the priest-baiting officers at the front) she is no nihilist. She lives by a definite, unshakeable value system, and what she values is love. During one of the many nights they spend together in Milan, the couple discusses marriage, which Henry wants but Catherine resists for practical reasons. It would necessitate their separation, she explains — more worldly than he, despite his battlefield experience. She reminds him and us of her having been formally engaged to the soldier who died. Then Catherine tells Henry that she has no religion. She quickly corrects this statement, however, explaining "You're my religion."
Catherine also tells the admitting nurse at the hospital where she goes to give birth at book's end that she lacks a formal religious affiliation of any kind. Henry too calls himself an agnostic, and yet, as virtually anyone would, Henry tries bargaining with God in his desperation at Catherine's impending death. Catherine, on the other hand, retains the courage of her convictions. To the very end, Catherine remains the somewhat stronger of the two. "Just you," she requests of Henry in response to his offer of a priest's visit. Despite everything, love is her religion until the instant she dies.
For much of the novel, Catherine is also more developed than Henry as a Hemingway hero, modest and truthful. Note that while Henry tolerates the "professional hero" Ettore Moretti, Catherine dislikes him intensely. "We have heroes too," Catherine says of Moretti, "But usually, darling, they're much quieter." Additionally, Catherine is distressed by the rigged racetrack betting in which Meyers is involved. "I don't like this crooked racing!" she declares. She suggests to Henry that they bet on a horse they've never heard of, and although it finishes fifth, she feels "so much cleaner." Again, while Henry is tolerant of a certain amount of corruption, Catherine demands purity.
