The word "correction" can be translated with a verbal phrase. The object of his "correction" is people. Alternate translation: "sometimes it happens to correct his people" (See: [[rc://en/ta/man/translate/figs-abstractnouns]] and [[rc://en/ta/man/translate/figs-explicit]])
This means that the rain waters the ground and causes vegetation to grow. Alternate translation: "sometimes to water the land" (See: [[rc://en/ta/man/translate/figs-explicit]])
The abstract noun "faithfulness" can be stated as "faithful" or "faithfully." Alternate translation: "sometimes to act faithfully to his covenant" or "sometimes to be faithful to his people" (See: [[rc://en/ta/man/translate/figs-abstractnouns]])