Tafsir of Al-Kahf 18:67

"He said, 'Indeed, you will never...'"

The negation of the ability to have patience is stated with emphasis, as if these matters are such that they cannot be correct or upright.

He justified this by the fact that he (Al-Khidr) undertakes affairs that are, in their outward appearance, reprehensible. How could a righteous man—let alone a Prophet—not feel revulsion, indignation, and distress when seeing such things, and thus proceed to object?

As for {khubran} (knowledge/information), it is a tamyiz (specifier). It means: "You have not encompassed it with your knowledge," in the sense of "you have not been informed of it." Its accusative case is that of an infinitive (masdar).