The first sin ever happened when the Great story of creation began when God wanted to create Adam. This indicates thst Iblis was the first sinner, not adam. God told the angels that:
…”Indeed, I will make upon the earth a successive authority…” [Qur’an 2:30] (1)
They said, “Will You place upon it one who causes corruption therein and sheds blood, while we exalt You with praise and declare Your perfection?” [Qur’an 2:30] (2)
because the angels didn’t know the wisdom beyond Adam’s creation, they asked God that, but God the Almighty replied:
He [Allah] said, “Indeed, I know that which you do not know.” [Qur’an 2:30] (3)
As from that creation will be the Prophets, Messengers, honest and good people.
Then God taught Adam the names – all of them.
And He showed them to the angels and said:
Then He showed them to the angels and said, “Inform Me of the names of these, if you are truthful.” [Qur’an 2:31] (4)
Angels immediately replied:
They said, “Exalted are You; we have no knowledge except what You have taught us. Indeed, it is You who is the Knowing, the Wise.” [Qur’an 2:32] (5)
Then God said:
He said, “O Adam, inform them of their names.” And when he had informed them of their names, He said, “Did I not tell you that I know the unseen [aspects] of the heavens and the earth? And I know what you reveal and what you have concealed.” [Qur’an 2:33] (6)
Angles are not talking (remaining silent)
Then God asked angels that:
And [mention] when We said to the angels, “Prostrate before Adam”; so they prostrated…” [Qur’an 2:34] (7)
The Big Twist Which Changed Everything
Is the story ended here when angels prostrated?
Actually No, A huge event happened, All angels prostrated except one of the Jin “who reached angels level of obeying God which is “Iblees”.
Iblees refrained to prostrate to Adam, as he was arrogant, venomous for Adam and became of the disbelievers.
So; God asked him:
[Allah] said, “O Iblees, what prevented you from prostrating to that which I created with My hands? Were you arrogant [then], or were you [already] among the haughty?” [Qur’an 38:75] (8)
He said, “I am better than him. You created me from fire and created him from clay” [Qur’an 38:76] (9)
God “Allah” commanded,
[Allah] said, “Then get out of it [i.e., Paradise], for indeed, you are expelled” [Qur’an 38:77] (10)
Did Iblees Realize the Fatal Mistake He Did?
No, he didn’t, Plus that Iblees became more conceited and appealed,
He said, “My Lord, then reprieve me until the Day they are resurrected.” [Qur’an 38:79] (11)
[Allah] said, “So indeed, you are of those reprieved. Until the Day of the time well-known.” [Qur’an 38:80-81] (12)
[Iblees] said, “By Your might, I will surely mislead them all. Except, among them, Your chosen servants.” [Qur’an 38:82-83] (13)
[Allah] said, “The truth [is My oath], and the truth I say. [That] I will surely fill Hell with you and those of them that follow you all together.” [Qur’an 38:84-85] (14)
Iblees didn’t stop at his level of disobedience for God. He also swore by God’s Power and Mighty to lead all Adam’s descendants astray to let them all enter hell in the hereafter.
After that God created Eve from Adam’s (side) to be his partner and enter Paradise with him.
God told them:
And We said, “O Adam, dwell, you and your wife, in Paradise and eat therefrom in [ease and] abundance from wherever you will…” [Qur’an 2:35](15)
But do not approach this tree, lest you be among the wrongdoers.”
Yet Iblees caused them to eat from that tree and slip out of paradise in which they had been.
…And We said, “Go down, [all of you], as enemies to one another, and you will have upon the earth a place of settlement and provision for a time.” [Qur’an 2:36] (16)
He said also:
Then Adam received from his Lord [some] words, and He accepted his repentance. Indeed, it is He who is the Accepting of Repentance, the Merciful. We said, “Go down from it, all of you. And when guidance comes to you from Me, whoever follows My guidance – there will be no fear concerning them, nor will they grieve. And those who disbelieve and deny Our signs – those will be companions of the Fire; they will abide therein eternally.” [Qur’an 2:37-39] (17)
However, God saw that Adam and Eve regretted their sin, So He taught them how to repent to Him.
Then Adam received from his Lord [some] words, and He accepted his repentance. Indeed, it is He who is the Accepting of Repentance, the Merciful.” [Qur’an 2:37] (18)
Iblees committed his sin before Adam peace be upon him committed his.
Adam and Eve repented to God and regretted what they made; however, Iblees did not. In addition to that, he acted arrogantly and haughtily in reaction to The Almighty God’s action.
Till now Iblees regrets this fatal sin every time the son of Adam recites the prostration in the noble Quran and prostrates.
Iblees (Satan) retires crying and says:
when, the son of Adam recites the Ayat of Sajdah (prostration) and then falls down in prostration, the Satan goes into seclusion and weeps and says: Alas, and in the narration of Abu Kuraib the words are: Woe unto me, the son of Adam was commanded to prostrate, and he prostrated and Paradise was entitled to him and I was commanded to prostrate, but I refused and am doomed to Hell.” [Hadith] (19)
Now, It’s your choice to REPENT or to REGRET.