The benefits of the saying of Allah the Exalted: << And he entered the city at a time when its people were unaware.

...Moses' entry into the city, his presence with the two men, and his killing of the soul—all of this was a cause for Moses' departure and then his prophethood. From this, it is derived that Allah (Glorified and Exalted is He) conducts affairs through causes. The affirmation of causes is derived from His saying: The permissibility of calling for aid from a created being, but it is prescribed only in what is beneficial; as for what is not beneficial, it is not permissible. Accordingly, if one calls for aid from a dead person, it is not permissible, because it does not benefit him. And if one calls for aid from a living person for something that person is unable to do, it is not permissible, because it does not benefit him. And if one calls for aid from a living person for something that person is able to do, it is permissible. Thus, calling for aid from a created being is permissible on the condition that it be in what is beneficial, and that it be from a living person capable of repelling the hardship. In it is also the affirmation of enmity and loyalty, due to His saying: This is a principle in the religion, for the loyalty of the believers is obligatory upon the believer, and disavowal of the disbelievers is obligatory upon the believer [Al-Mumtahanah:4]. This is a matter that is necessary: that a person must disavow every disbeliever.
In the verse is evidence of Moses' strength, due to His saying: In it is the affirmation of his jealousy and his quick response, for he did not hesitate in the matter but rather hastened to it. Is it derived from this the permissibility of repelling an aggressor to the extent of killing?
The students: ...

The Shaykh : ...But in the Islamic Shari'ah, it is known that if a person attacks someone and he repels him with the best manner, and he is not repelled, then he has the right to kill him.
In it is: that sins are from the commands and deeds of Satan, due to His saying: .
In it is also the affirmation of causality, due to His saying: because of causality.
In it is also the establishment of Satan's enmity toward the children of Adam and it was emphasized with to strongly deter from him, because there is no ambiguity in his enmity.