When did Iblis become a disbeliever?
When he refused to fall down prostrate to the being Allah created out of mire.
When thy Lord said unto the angels: Lo! I am about to create a mortal out of mire,
And when I have fashioned him and breathed into him of My Spirit, then fall down before him prostrate,
When I'm done with that, fall down before him prostrate.
The angels fell down prostrate, every one,
Saving Iblis; he was scornful and became one of the disbelievers.
38:71
