Repenting is spoken of as if it were physically returning to Yahweh. This can be stated in active form. Alternate translation: "I will save you from your enemies if you will repent and rest knowing that I will take care of you" (See: [[rc://en/ta/man/translate/figs-metaphor]] and [[rc://en/ta/man/translate/figs-activepassive]])
Quietness here refers to not being anxious and worried. It is implied that they are not worried because they trust in Yahweh. Alternate translation: "You will be strong if you are quiet and trust in me" (See: [[rc://en/ta/man/translate/figs-explicit]])