Islam As Defined in the Qur'anIslam, also called in the Quran “Din Hanif, i.e Deism” promotes truth seeking based on natural evidences, fairness, facts and universal truths. It is also reported that the Prophet said: "إني لم أبعث باليهودية ولا بالنصرانية ولكني بعثت بالحنيفية " I have not been sent to either Judaism or Christianity but I have been sent towards Hanifiyya. Therefore all focus of the Prophet remained towards Hanifiyya, many of them lived around Makkah and others happened to vist on Hajj, Umrah and for trade. This explains the repeated instruction to the Prophet in the Qur'an not to worry about the rejection or opposition of the elite of Makkah and keep your attention towards people, Hanifs, who listen to you. Quran asserts that Islam is the pure Din of Prophet Ibrahim revived by Prophet Mohammad SAW. The following verses of the Qur’an clarify the stand of Islam and the mission of prophet Mohammad SAW.
قُلْ إِنَّنِي هَدَانِي رَبِّي إِلَىٰ صِرَاطٍ مُّسْتَقِيمٍ دِينًا قِيَمًا مِّلَّةَ إِبْرَاهِيمَ حَنِيفًا
Say (O Prophet SAW): Lo! As for me, my Lord hath guided me unto a straight path, a right faith, the community of Abraham, the upright (Hanif),Sura Al-Anaam 6, Verse 161)
Charcteristics of Hanif people mentioned in the Quran and Arab history make it clear that they included leaders of the enlightenment movements, iconoclasts, reformers, Stoics and classical Deists.
فَأَقِمْ وَجْهَكَ لِلدِّينِ حَنِيفًا ۚ فِطْرَتَ اللَّـهِ الَّتِي فَطَرَ النَّاسَ عَلَيْهَا ۚ لَا تَبْدِيلَ لِخَلْقِ اللَّـهِ ۚ ذَٰلِكَ الدِّينُ الْقَيِّمُ وَلَـٰكِنَّ أَكْثَرَ النَّاسِ لَا يَعْلَمُونَ ﴿٣٠﴾ مُنِيبِينَ إِلَيْهِ وَاتَّقُوهُ وَأَقِيمُوا الصَّلَاةَ وَلَا تَكُونُوا مِنَ الْمُشْرِكِينَ ﴿٣١﴾ سورة الروم
And so, set thy face steadfastly towards the [Din Hanif] natural faith, the natural disposition which God has instilled into man: not to change to corrupt what God has thus created, the ever-true faith; but most people know it not. (30) turning unto Him [alone]; and remain conscious of Him, and be constant inprayer, and be not among those who ascribe divinity to aught beside Him, (31)
يَٰأَيُّهَا ٱلَّذِينَ آمَنُواْ كُونُواْ قَوَّٰمِينَ بِٱلْقِسْطِ شُهَدَآءَ للَّهِ وَلَوْ عَلَىۤ أَنْفُسِكُمْ أَوِ ٱلْوَٰلِدَيْنِ وَٱلأَقْرَبِينَ إِن يَكُنْ غَنِيّاً أَوْ فَقِيراً فَٱللَّهُ أَوْلَىٰ بِهِمَا فَلاَ تَتَّبِعُواْ ٱلْهَوَىٰ أَن تَعْدِلُواْ وَإِن تَلْوُواْ أَوْ تُعْرِضُواْ فَإِنَّ ٱللَّهَ كَانَ بِمَا تَعْمَلُونَ خَبِيراً
O you who believe! Be you staunch in justice (right, truth), witnesses for Allah, even though it be against yourselves or (your) parents or (your) kindred, whether (the case be of) a rich man or a poor man, for Allah is nearer unto both . So follow not passion lest you lapse (from truth) and if you lapse or fall away, then lo! Allah is ever informed of what you do. (An-Nisa, Chapter4, Verse135)
قُلْ هَـٰذِهِ سَبِيلِي أَدْعُو إِلَى اللَّـهِ ۚ عَلَىٰ بَصِيرَةٍ أَنَا وَمَنِ اتَّبَعَنِي ۖ وَسُبْحَانَ اللَّـهِ وَمَا أَنَا مِنَ الْمُشْرِكِينَ ﴿١٠٨﴾ سورة يوسف
Say [O Prophet]: "This is my way: Resting upon conscious insight accessible to reason, I am calling [you all] unto Allah - I and they who follow me." And [say:] "Limitless is Allah in His glory; and I am not one of those who ascribe divinity to aught beside Him!" (108)
Quran has detailed the story of Prophet Ibrahim where he being an upright rational truth seeker discovered Islam (Din Hanif), despite being born in an idolatrous family. He is described to reach monotheistic faith in the benevolent omnipotent creator based on his rational observations evident in nature, fairness, facts and universal truths. Ibrahim is quoted in the Qur'an telling his Hanif (deistic) faith to his nation :
قَالَ يَا قَوْمِ إِنِّي بَرِيءٌ مِّمَّا تُشْرِكُونَ ﴿٧٨﴾إِنِّي وَجَّهْتُ وَجْهِيَ لِلَّذِي فَطَرَ السَّمَاوَاتِ وَالْأَرْضَ حَنِيفًا ۖ وَمَا أَنَا مِنَ الْمُشْرِكِينَ ﴿٧٩﴾
I am quit of that you associate. (78)I have turned my face to Him who originated the heavens and the earth, a man of pure faith; I am not of the idolaters.' (Sura Al-Anaam 6, Verse79)
Hanif, from:The concept of Allāh as the highest God in pre-Islamic Arabia : a study of pre-Islamic Arabic religious poetry,
https://escholarship.mcgill.ca/concern/theses/6w924d58s, McGill University, Institute of Islamic Studies, Master of Arts Thesis, 1999