Shall not God search this out? for he knows the secrets of the heart.
Read Chapter 44
Augustine of Hippo
16. "If we have forgotten the Name of our God." Here is the "understanding" of the "sons of Korah." "And stretched out our hands to a strange God" (ver. 20). "Shall not God search this out? For He knoweth the secrets of the heart" (ver. 21). He "knows," and yet He "searches them out"? If He knows the secrets of the heart, what do the words, "Shall not God search it out," do there? He "knows" it in Himself; He "searches it out" for our sakes. For it is for this reason God sometimes "searches a thing out;" and speaks of that becoming known to Himself, which He is Himself making known to thee. He is speaking of His own work, not of His knowledge. We commonly say, "A gladsome day," when it is fine. Yet is it the day itself that experiences delight? No: we speak of the day as gladsome, because it fills us with delight. And we speak of a "sullen sky." Not that there is any such feeling in the clouds, but because men are affected with sullenness at the sight of such an appearance of the skies...
Slaughter. They will not suffer us to be quiet respecting our religion, striving to delude us: or, if we prove resolute, like Daniel, they expose us to torments. (Calmet)
This was more fully verified at the first propagation of the gospel, (Romans viii. 36.) as it still continues to be among those, who cease not to persecute Catholics by artifice, as well as by open violence. Christians in every age (Haydock) are persecuted, more than the prophets (Worthington) generally were. (Haydock)