The means of awareness of issues are either knowledge, tradition, doubt, suspicion, or illusion. Of course, knowledge is the highest level among these. Allah (swt) says:

{ وَمَا اخْتَلَفَ الَّذِينَ أُوتُوا الْكِتَابَ إِلَّا مِن بَعْدِ مَا جَاءَهُمُ الْعِلْمُ }

(And those who were given the Scripture did not differ except after knowledge had come to them) (Ali-Imran: 19)

In this verse Allah (swt) does not mention that they differed because of their doubt, ignorance, or suspicion or illusion, rather they differed after they have fully received the knowledge.

Allah (swt) reminds them that their thinking is not true at all, rather it is suspicion does not reach the level of certainty.

بَلَىٰ  (Yes): Is an article of answering as “Verify” but used to express a negative answer, meaning that it denies what preceded it. Here it denies his suspicion that (he would never return) and indeed he would return to his Lord.

His Lord was ever watchful of him, All-Knowing and All-Aware of all his deeds, nothing is hidden from Him. No one can flee from Allah (swt) or hide from Him because Allah (swt) is All-Knowing of all his movements. Allah (swt) says: