There is this passage from the Doctrine of the Mean:
""Hence the sovereign may not neglect the cultivation of his own character. Wishing to cultivate his character, he may not neglect to serve his parents. In order to serve his parents, he may not neglect to acquire knowledge of men. In order to know men, he may not dispense with a knowledge of Heaven" (link)
Below is a passage refering to this text:
...然苟不知人所以為人之理,則亦無以事其親。而理本出於天,故曰不可以不知人不知天。此所謂人,與仁者人也之人,正相發。恐非指賢者也。
I am not sure how to understand this phrase: "正相發". Any help would be greatly appreciated.