RobH_en_tn/1pe/02/08.md

A stone of stumbling and a rock that makes them fall

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/translate/figs-explicit and rc://en/ta/man/translate/figs-parallelism and rc://en/ta/man/translate/figs-metaphor)

stumble because they disobey the word

Here "the word" refers to the gospel message. To disobey means that they do not believe. "stumble because they are not believing the message about Jesus"

which is what they were appointed to do

This can be stated in active form. Alternate translation: "for which God also appointed them" (See: rc://en/ta/man/translate/figs-activepassive)