"You who have such little faith." Jesus is scolding the people because they have little faith in God. See how you translated this in [Matthew 6:30](../06/30.md).
Jesus uses a question to tell Peter than he should not have doubted. You can make explicit what Peter should not have doubted. AT: "you should not have doubted that I could keep you from sinking" (See: [[rc://en/ta/man/translate/figs-rquestion]] and [[rc://en/ta/man/translate/figs-explicit]])