وَجَحَدُوا بِهَا وَاسْتَيْقَنَتْهَا أَنْفُسُهُمْ ظُلْمًا وَعُلُوًّا
They denied them, although their souls were convinced of them, out of injustice and arrogance. (Qur'an 27:14)
Some theologians draw from this verse a distinction between mere certainty of fact and faithful acknowledgment. A person may recognize evidence and yet persist in rejection through pride or obstinacy.
The principle does not authorize us to claim certain knowledge of any contemporary individual's inner state. The verse describes a particular case of knowing the truth without receiving it in obedient acceptance.