The reason for mentioning killing after the prohibition of obscenities

Question:
Honorable Shaykh, Allah the Exalted said: Then He said: Is not killing among the grave sins? What is the reason for mentioning grave sins specifically, to the exclusion of others, in this world?

Answer:
Yes, He prohibited the major sins in general, and then He prohibited killing specifically, even though it is included among the major sins, in order to emphasize the prohibition of killing. In order to emphasize the prohibition of killing, and to magnify the status of killing and its danger. This is called, in the category of emphasis, mentioning a thing first along with others, and then mentioning it alone. So, His saying, the Exalted: means that the Asr prayer is included in them, and then He specified the Asr prayer and said "and the middle prayer" to indicate its importance, just as He said, the Exalted: There is no doubt that Jibril and Mikail are included among the angels, but mentioning them separately is in the category of emphasis regarding them (peace be upon them), due to their excellence over the rest of the angels.
So a thing may be mentioned twice: once along with others, and once alone, for emphasis. Like killing here, where He prohibited it along with obscenities, then mentioned it alone in the category of emphasizing its status and that it is dangerous. And because it frequently occurs among people, who are lenient with it, so He emphasized the prohibition of it.