The One Who believes in the Qur'an is upon Clear Proof from His Lord
Allah, the Exalted says,
أفمن كان على بينة من ربه
Can they who rely on a clear proof from their Lord,
Allah, the Exalted, informs of the condition of the believers who are upon the natural religion of Allah, which He made inherent in His creatures. This is based upon their confession to Him that there is none worthy of worship except He.
This is similar to Allah's statement,
فٲقم وجهك للدين حنيفا فطرة الله التى فطر الناس عليها
So set you your face towards the religion, Hanifan. Allah's Fitrah with which He has created mankind. (30:30),
In the Two Sahihs it is recorded that Abu Hurayrah said that the Messenger of Allah said,
كل مولود يولد على الفطرة فٲبواه يهودانه أو ينصرانه أو يمجسانه كما تولد البهيمة بهيمة جمعاء هل تحسون فيها من جدعاء
Every child is born upon the Fitrah, but his parents make him a Jew, Christian, or Magian. This is just as the calf that is born whole. Have you noticed any calves that are born mutilated?
In Sahih Muslim it is recorded that Iyad bin Himar said that the Messenger of Allah said,
يقول الله تعالى
إني خلقت عبادي حنفاء فجاءتهم الشياطين فاجتالتهم عن دينهم وحرمت عليهم ما أحللت لهم وأمرتهم أن يشركوا بي ما لم أنزل به سلطانا
Allah, the Exalted, says,
`Verily, I created my servants Hunafa', but the devils came to them and distracted them from their religion. They made unlawful for them what I had made lawful for them and they commanded them to associate partners with Me, concerning which no authority has been revealed.
Therefore, the believer is one who remains upon this Fitrah.
Concerning Allah's statement,
ويتلوه شاهد منه
and whom a witness from Him recites (follows) it;
This means that a witness comes to him from Allah. That witness is the pure, perfect and magnificent legislation that Allah revealed to the Prophets. These legislations were finalized with the legislation (Shariah) of Muhammad. The believer has the natural disposition that bears witness to (the truth of) the general legislation, and accepts that specific laws are taken from the general legislation. The Fitrah accepts the Shariah and believes in it.
For this reason Allah, the Exalted, says,
أفمن كان على بينة من ربه ويتلوه شاهد منه
(Can they who rely on a clear proof from their Lord, and whom a witness from Him recites (follows) it);
This clear proof which is recited is the Qur'an, which Jibril conveyed to the Prophet and the Prophet Muhammad conveyed it to his Ummah.
Then Allah says,
ومن قبله كتاب موسى
and before it, came the Book of Musa,
This means that before the Qur'an, there was the Book of Musa, the Tawrah.
إماما ورحمة
a guidance and a mercy,
This means that Allah, the Exalted, revealed it to that Ummah as a leader for them and a guide for them to follow, as a mercy from Allah upon them. Therefore, whoever believed in it with true faith, then it would lead him to believe in the Qur'an as well.
For this reason Allah said,
أوليك يومنون به
they believe therein.
Then Allah, the Exalted, threatens those who reject the Qur'an, or any part of it, by saying,
ومن يكفر به من اﻻحزاب فالنار موعده
but those of the sects that reject it, the Fire will be their promised meeting place.
This is directed towards everyone on the face of the earth who disbelieves in the Qur'an, whether they are idolators, disbelievers, People of the Scripture, or other sects from the descendants of Adam. This applies to all whom the Qur'an reaches, regardless of their differences in color, appearance, or nationality.
As Allah says,
ﻻنذركم به ومن بلغ
that I may therewith warn you and whomsoever it may reach. (6:19)
Allah, the Exalted, said,
قل يٲيها الناس إنى رسول الله إليكم جميعا
Say: "O mankind! Verily, I am sent to you all as the Messenger of Allah.''
Allah says,
ومن يكفر به من اﻻحزاب فالنار موعده
(but those of the sects that reject it, the Fire will be their promised meeting place).
In Sahih Muslim it is recorded that Abu Musa Al-Ash`ari, may Allah be pleased with him, said that the Messenger of Allah said,
والذي نفسي بيده ﻻ يسمع بي أحد من هذه اﻻمة يهودي أو نصراني ثم ﻻ يومن بي إﻻ دخل النار
By He in Whose Hand is my soul! there is no one of this Ummah, whether he be a Jew or Christian, who hears of me and does not believe in me, except that he will enter the Hell- fire.
Every Hadith is confirmed by the Qur'an
Ayub As-Sakhtiyani reported from Sa`id bin Jubayr that he said,
"I did not hear any Hadith of the Prophet, substantiated as he stated it, except that I found its confirmation in the Qur'an.
The narrator said, "Or he said, `I found its verification in the Qur'an.'''
Thus, it reached me that the Prophet said,
ﻻ يسمع بي أحد من هذه اﻻمة يهودي وﻻ نصراني ثم ﻻ يومن بي إﻻ دخل النار
There is no one of this Ummah, whether he be a Jew or Christian, who hears of me and does not believe in me, except that he will enter the Hellfire.
Therefore, I said, `Where is its verification in the Book of Allah? Most of what I have heard reported from the Messenger of Allah, I have found its verification in the Qur'an.'
Then I found this verse,
ومن يكفر به من اﻻحزاب فالنار موعده
(but those of the sects that reject it (the Qur'an), the Fire will be their promised meeting place). And this means from all religions.''
Then Allah says,
فﻼ تك في مرية منه إنه الحق من ربك
So be not in doubt about it. Verily, it is the truth from your Lord,
This means that the Qur'an is the truth from Allah and there is no doubt or suspicion concerning it.
This is as Allah says,
الم
تنزيل الكتاب ﻻ ريب فيه من رب العالمين
Alif Lam Mim. The revelations of the Book in which there is no doubt, is from the Lord of all that exists! (32:1-2)
Allah, the Exalted, says,
ا
لم
ذلك الكتاب ﻻ ريب فيه
Alif Lam Mim. This is the Book in which there is no doubt. (2:1-2)
The Ayah;
ولكن أكثر الناس ﻻ يومنون
but most of mankind believe not.
is similar to Allah's statement,
وما أكثر الناس ولو حرصت بمومنين
And most of mankind will not believe even if you desire it eagerly. (12:103)
Likewise, Allah says,
وإن تطع أكثر من فى اﻻرض يضلوك عن سبيل الله
And if you obey most of those on the earth, they will mislead you far away from Allah's path.
Allah also says,
ولقد صدق عليهم إبليس ظنه فاتبعوه إﻻ فريقا من المومنين
And indeed Iblis did prove true his thought about them: and they followed him, all except a group of true believers. (34:20)