BismiLlahir Rahmaanir Raheem
Iblis disobeyed Allah (tabaarak wa ta'ala) and became defiant. He arrogantly refused to accept the authority of a creature who was made of rubbish. Iblis thought himself superior to human being. As a result, Allah (jalla wa 'ala) expelled him from the Garden of Bliss and deprived him of all Divine favours. Satan requested Almighty Allah (subhanaho wa ta'ala) to allow him to exist until the Day of judgement.
"I will bring most of the descendants of Adam under my sway. I will lead them astray from the right path." he had said.
Allah (tabaarak wa ta'ala) gave him respite. The conversation between Allah (jalla wa 'ala) and Iblis has been narrated in the Holy Qur'an as follows:
"Iblis said: Give me respite till the Resurrection Day. Allah said: Be you among those who are given respite. He said: Because You have thrown me out of the way, i will certainly lie in wait for them on Your Straight Path. Then i will assault them from before them and behind them, from their right and from their left, nor will You find most of them grateful." ~(7:14-18)
Devil is, in fact, an evil spirit which tempts the man to indulge in sins. It invites the heart to do bad deeds and disobey Allah (azza wa jal). It tries to weaken our sense of morality but if we are spiritually too strong to yield to its temptations, we become immune from all sins. Those who follow the Commandments of Allah (subhanaho wa ta'ala), invite Allah's grace to protect them. On the other hand, those who deliberately follow the wrong way, are responsible because they put themselves into the hands of Evil spirits.