The verbs "revealed" and "made known" mean basically the same thing. Paul uses both of them to emphasize his point. You can combine these words and translate this in an active form. Alternate translation: "but now the eternal God has made it known to all the nations through the prophetic writings" (See: [[rc://en/ta/man/translate/figs-doublet]] and [[rc://en/ta/man/translate/figs-activepassive]])
Here "obedience" and "faith" are abstract nouns. You can use the verbs "obey" and "trust" in your translation. You may need to make explicit who will obey and trust. Alternate translation: "so that all nations will obey God because they trust in him" (See: [[rc://en/ta/man/translate/figs-abstractnouns]] and [[rc://en/ta/man/translate/figs-explicit]])