Al-Ḥāriṯ

Al-Ḥāriṯ (literally: the lion, the ploughman, or the light-bringer, anglicised as Ateras, Atheras, Eosphorus, Phosphorus, and Lucifer), known as Azazil (literally "the Dear of God", anglicised as Azezel), is the Satan from Islamic scriptures. He was pious genie and due to that he ascended from his demonic state as one of jinn to worship Allah with his angels; however, when he refuse to prostration for Adam he transformed to something worse and more demonic and became the father of devils.

In the Quran
Al-Harith never mentioned by his name in the Quran but in the Sunnah, instead: he is mentioned by the title Iblis which translated directly as Satan or al-Shaitan (the Devil)

chapter 15 verse 28-44

Waith qala rabbuka lilmalaikati innee khaliqun basharan min salsalin min hamain masnoonin ( 28 )

وَإِذْ قَالَ رَبُّكَ لِلْمَلَائِكَةِ إِنِّي خَالِقٌ بَشَرًا مِنْ صَلْصَالٍ مِنْ حَمَإٍ مَسْنُونٍ ﴿ 28 ﴾

Behold! thy Lord said to the angels: "I am about to create man, from sounding clay from mud moulded into shape;

Faitha sawwaytuhu wanafakhtu feehi min roohee faqaAAoo lahu sajideena ( 29 )

فَإِذَا سَوَّيْتُهُ وَنَفَخْتُ فِيهِ مِنْ رُوحِي فَقَعُوا لَهُ سَاجِدِينَ ﴿ 29 ﴾

"When I have fashioned him (in due proportion) and breathed into him of My soul, fall ye down in obeisance unto him."

Fasajada almalaikatu kulluhum ajmaAAoona ( 30 )

فَسَجَدَ الْمَلَائِكَةُ كُلُّهُمْ أَجْمَعُونَ ﴿ 30 ﴾

So the angels prostrated themselves, all of them together:

Illa ibleesa aba an yakoona maAAa alssajideena ( 31 )

إِلَّا إِبْلِيسَ أَبَىٰ أَنْ يَكُونَ مَعَ السَّاجِدِينَ ﴿ 31 ﴾

Not so Iblis: he refused to be among those who prostrated themselves.

Qala ya ibleesu ma laka alla takoona maAAa alssajideena ( 32 )

قَالَ يَا إِبْلِيسُ مَا لَكَ أَلَّا تَكُونَ مَعَ السَّاجِدِينَ ﴿ 32 ﴾

((Allah)) said: "O Iblis! what is your reason for not being among those who prostrated themselves?"

Qala lam akun liasjuda libasharin khalaqtahu min salsalin min hamain masnoonin ( 33 )

قَالَ لَمْ أَكُنْ لِأَسْجُدَ لِبَشَرٍ خَلَقْتَهُ مِنْ صَلْصَالٍ مِنْ حَمَإٍ مَسْنُونٍ ﴿ 33 ﴾

(Iblis) said: "I am not one to prostrate myself to man, whom Thou didst create from sounding clay, from mud moulded into shape."

Qala faokhruj minha fainnaka rajeemun ( 34 )

قَالَ فَاخْرُجْ مِنْهَا فَإِنَّكَ رَجِيمٌ ﴿ 34 ﴾

((Allah)) said: "Then get thee out from here; for thou art rejected, accursed.

Wainna AAalayka allaAAnata ila yawmi alddeeni ( 35 )

وَإِنَّ عَلَيْكَ اللَّعْنَةَ إِلَىٰ يَوْمِ الدِّينِ ﴿ 35 ﴾

"And the curse shall be on thee till the day of Judgment."

Qala rabbi faanthirnee ila yawmi yubAAathoona ( 36 )

قَالَ رَبِّ فَأَنْظِرْنِي إِلَىٰ يَوْمِ يُبْعَثُونَ ﴿ 36 ﴾

(Iblis) said: "O my Lord! give me then respite till the Day the (dead) are raised."

Qala fainnaka mina almunthareena ( 37 )

قَالَ فَإِنَّكَ مِنَ الْمُنْظَرِينَ ﴿ 37 ﴾

((Allah)) said: "Respite is granted thee

Ila yawmi alwaqti almaAAloomi ( 38 )

إِلَىٰ يَوْمِ الْوَقْتِ الْمَعْلُومِ ﴿ 38 ﴾

"Till the Day of the Time appointed."

Qala rabbi bima aghwaytanee laozayyinanna lahum fee alardi walaoghwiyannahum ajmaAAeena ( 39 )

قَالَ رَبِّ بِمَا أَغْوَيْتَنِي لَأُزَيِّنَنَّ لَهُمْ فِي الْأَرْضِ وَلَأُغْوِيَنَّهُمْ أَجْمَعِينَ ﴿ 39 ﴾

(Iblis) said: My Lord, Because Thou has sent me astray, I verily shall adorn the path of error for them in the earth, and shall mislead them every one.

Illa AAibadaka minhumu almukhlaseena ( 40 )

إِلَّا عِبَادَكَ مِنْهُمُ الْمُخْلَصِينَ ﴿ 40 ﴾

"Except Thy servants among them, sincere and purified (by Thy Grace)."

Qala hatha siratun AAalayya mustaqeemun ( 41 )

قَالَ هَٰذَا صِرَاطٌ عَلَيَّ مُسْتَقِيمٌ ﴿ 41 ﴾

((Allah)) said: "This (way of My sincere servants) is indeed a way that leads straight to Me.

Inna AAibadee laysa laka AAalayhim sultanun illa mani ittabaAAaka mina alghaweena ( 42 )

إِنَّ عِبَادِي لَيْسَ لَكَ عَلَيْهِمْ سُلْطَانٌ إِلَّا مَنِ اتَّبَعَكَ مِنَ الْغَاوِينَ ﴿ 42 ﴾

"For over My servants no authority shalt thou have, except such as put themselves in the wrong and follow thee."

Wainna jahannama lamawAAiduhum ajmaAAeena ( 43 )

وَإِنَّ جَهَنَّمَ لَمَوْعِدُهُمْ أَجْمَعِينَ ﴿ 43 ﴾

And verily, Gehenna is the promised abode for them all!

Laha sabAAatu abwabin likulli babin minhum juzon maqsoomun ( 44 )

لَهَا سَبْعَةُ أَبْوَابٍ لِكُلِّ بَابٍ مِنْهُمْ جُزْءٌ مَقْسُومٌ ﴿ 44 ﴾

To it are seven gates: for each of those gates is a (special) class (of sinners) assigned.

As a fallen angel
Some said al-Harith was paradisiac angel, Watcher, cherub, or seraph before his dismissal from paradise; then, he turned into a devil, genie, or devilish genie.

Some people mistakenly thought jinn were the angels of paradise and considered jinn as type of angels or fallen angels.

He possibly born as a genie then turned into angel then fall from his grace.

But unlike Christian fallen angels, Islamic fallen angels are redeemable and can get their graces back.

As a genie
He is either born as genie then turned into devil, or born as angel then transformed into genie as punishment for his wrong deeds. In other stories he was always a genie and never was an angel.

In Yazidism
There is an angel similar to Iblis in Yazidi mythology called: Peacock Angel;. Such angels ordered by God to prostration for Adam all angels prostrated but Peacock Angel refused because he didn't want to prostration for anyone rather than God. Due to that, he promoted to leader of angels as reward; unlike al-Harith, he didn't became Iblis or anything like that.

In Sufism
Al-Harith is either another name of Marra, his son, or his father.