ভূমিকা
General Comment It has been explained earlier that the preceding words, “and what you were hiding”, show that there was a hidden thing that had, meanwhile, come into open. The last sentence of this verse too leads to the same conclusion. Instead of saying, “He refused and he showed arrogance, and he disbelieved”, it says, “. . . he was one of the unbelievers”.
It was not that he became an unbeliever at that moment; he was an unbeliever long since, but had kept it a secret, and this event brought it into open. Also, it was mentioned that the event of the prostration of the angels must have happened between the divine words, “Surely I know what you do not know”, and the words, ”. . . I know what you manifest and what you were hiding”. It may be asked: Why then has Allah put this verse after those words?
Probably it has been done just to create a link between the stories of creation of Adam and his being placed in the Paradise. The twelve verses (28-39) were revealed to describe how and when man was made vicegerent of Allah, how was he sent down to the earth, and what is to happen to him in this life - the happenings that will have a bearing on his lasting happiness or unhappiness. For this theme, the event of prostration has not much importance - except as a connecting link.
That is why it has been mentioned here only briefly without going into details. Perhaps, it is because of the same reason that the Qur'an has changed the pronouns referring to Allah from the third person ( your Lord said ) to the first ( And when We said ) . The angels had not hidden anything from Allah; it was Iblīs who had done so. Then why did Allah ascribe this deed to all of them ( you were hiding )?
Allah in this talk used the same method which even the human beings have adopted for their own speeches; we ascribe the work of an individual to the whole group, if the doer is not properly identified or if he tries to remain anonymous. Also, there may be another explanation for it.