But that your earnest care for us might be made manifest (all' heineken tou phanerōthēnai tēn spoudēn humōn tēn huper hēmōn). So the correct text, not “our care for you.” Easy to interchange Greek humōn (your) and hēmōn (our). Usual construction with preposition heneken and genitive of articular infinitive with accusative of general reference.