Tafsir of Al-Hijr 15:69

(Meaning: Do not humiliate me, and do not insult me by subjecting those whom I have granted sanctuary to harm, for that is al-khizy—meaning abasement and disgrace.)

Since their molestation of them—after he had forbidden them by saying, "and do not expose me"—is more impactful upon his standing (peace be upon him) and brings greater shame upon him—for molestation of a guest before being informed of his status might be overlooked, but after being informed and openly declaring his protection of them, the sin is far greater and constitutes the ultimate disgrace—he (peace be upon him) expressed what he would suffer from their side after the aforementioned prohibition due to their obstinacy and open defiance of him by using the term al-khizy (disgrace), and he commanded them to fear Allah, the Exalted, regarding that.

It is also possible that it refers to al-khazayah, which is shame; meaning: do not cause me to be ashamed before people by your molestation of them. Some scholars consider the first interpretation more likely.

As for why he (peace be upon him) did not explicitly forbid the act of immorality itself, it has been said: because he knew that such a prohibition would be of no benefit to them. It has also been said: it was out of regard for the utmost politeness toward his guests, as he did not explicitly state that which would be heavy upon their hearing and from which their natures would recoil—for the free man considers death more palatable than such base desire.

Some eminent scholars have said: the intent behind "fear Allah" is a command for them to fear Him—sublime is He—against committing that immorality. This is challenged by the fact that its placement between two prohibitions relating to his own person (peace be upon him) does not support this, and likewise [does it conflict with] the saying of the Exalted...