These two phrases share similar meanings. Together they emphasize that people will take offense at this "stone," which refers to Jesus. Alternate translation: "a stone or a rock over which people will stumble" (See: [[rc://en/ta/man/jit/figs-explicit]] and [[rc://en/ta/man/jit/figs-parallelism]] and [[rc://en/ta/man/jit/figs-metaphor]])
Here "the word" refers to the gospel message. To disobey means to not believe. Alternate translation: "stumble because they do not believe the message about Jesus"