The Satan has played the worst  role in the sin that both Adam and Eve had fallen in, before persuading Adam and Eve to disobey God, he himself committed a sin before God when he disobeyed God, Man and Satan, like all the other creatures were created for a certain goal:

I have only created Jinns and men, that they may serve Me. (56) No Sustenance do I require of them, nor do I require that they should feed Me. (57) For Allah is He Who gives (all) Sustenance,- Lord of Power,- Steadfast (for ever).(51:65-58)

Knowing this sin reveals how big the enmity between man and the Satan was and still is. It is known that the first creature that disobeyed God was the Satan about whom the Quran says what means:

Behold! We said to the angels, "Bow down to Adam": They bowed down except Iblis. He was one of the Jinns, and he broke the Command of his Lord. Will ye then take him and his progeny as protectors rather than Me? And they are enemies to you! Evil would be the exchange for the wrong-doers! (19:50)

So according to the above mentioned verse, the Satan was from among the angels, some expounders say that he was from the Jinns but got a higher rank  similar to that of the angels because of his much worship. However, the Holy Book considers it from among the angels.

The core meaning of worship is the submission to the order of God, a righteous person should not discuss the orders of God as he is always imperfect in the sense that there are many things out his perception. The Holy Quran has describes succinctly the pride and haughtiness of the Satan in the following verse:

And behold, We said to the angels:

"Bow down to Adam" and they bowed down. Not so Iblis: he refused and was haughty: He was of those who reject Faith. (2:34)

In the following verse the Satan showed why he considered itself better than Adam, it brazenly argues with the Creator Whom we all should submit to. Think about the impolite language it used while it talked to the Lord Who created it.

Behold! We said to the angels: "Bow down unto Adam": They bowed down except Iblis: He said,

"Shall I bow down to one whom Thou didst create from clay?" He said: "Seest Thou? this is the one whom Thou hast honoured above me! If Thou wilt but respite me to the Day of Judgment, I will surely bring his descendants under my sway - all but a few!" (17:61-62)

However the way the Satan argued with God and even the way he refused to submit to His Creator showed to what extent the Satan is imprudent.

Behold! We said to the angels, "Bow down to Adam": They bowed down except Iblis. He was one of the Jinns, and he broke the Command of his Lord. Will ye then take him and his progeny as protectors rather than Me? And they are enemies to you! Evil would be the exchange for the wrong-doers!

 The consequence the Satan brought on itself is so great; it is detailed in the following verse:

Behold! thy Lord said to the angels:

"I am about to create man, from sounding clay from mud moulded into shape; "When I have fashioned him (in due proportion) and breathed into him of My spirit, fall ye down in obeisance unto him."So the angels prostrated themselves, all of them together: Not so Iblis: he refused to be among those who prostrated themselves. (31) (Allah) said: "O Iblis! what is your reason for not being among those who prostrated themselves?" (32)(Iblis) said: "I am not one to prostrate myself to man, whom Thou didst create from sounding clay, from mud moulded into shape." (33)(Allah) said: "Then get thee out from here; for thou art rejected, accursed. (34)"And the curse shall be on thee till the Day of Judgment."