Exegesis of the saying of Allah the Exalted: “Indeed, it is they who are the corrupters, but they do not perceive”

But Allah responded to them by saying: He responded to them with a strong response. What made it strong? First: the introductory particle “ala” which serves as a warning and an emphasis. Second: “inna” which indicates emphasis. Third: “hum” which is a separating pronoun that serves as a restriction and an emphasis. So Allah (Mighty and Majestic) said: “Indeed, it is they alone who are the corrupters, but they do not perceive their corruption, for they, may Allah protect us from that, have had their hearts sealed, so they have no awareness.”