Ibn Kathir
وَلَن تَرْضَى عَنكَ الْيَهُودُ وَلاَ النَّصَـرَى حَتَّى تَتَّبِعَ مِلَّتَهُمْ
(Never will the Jews nor the Christians be pleased with you (O Muhammad ) till you follow their religion.) meaning, `The Jews and the Christians will never be happy with you, O Muhammad! Therefore, do not seek what pleases or appeases them, and stick to what pleases Allah by calling them to the truth that Allah sent you with.' Allah's statement,
قُلْ إِنَّ هُدَى اللَّهِ هُوَ الْهُدَى
(Say: "Verily, the guidance of Allah (i.e. Islamic Monotheism) that is the (only) guidance") emeans, `Say, O Muhammad , the guidance of Allah that He sent me with is the true guidance, meaning the straight, perfect and comprehensive religion."' Qatadah said that Allah's statement,
قُلْ إِنَّ هُدَى اللَّهِ هُوَ الْهُدَى
(Say: "Verily, the guidance of Allah (i.e. Islamic Monotheism) that is the (only) guidance) is, "A true argument that Allah taught Muhammad and his Companions and which they used against the people of misguidance." Qatadah said, "We were told that the Messenger of Allah ﷺ used to say,
«لَا تَزَالُ طَائِفَةٌ مِنْ أُمَّتِي يُقَاتِلُونَ عَلَى الْحَقِّ ظَاهِرِينَ، لَا يَضُرُّهُمْ مَنْ خَالَفَهُمْ حَتَّى يَأْتِيَ أَمْرُ الله»
(There will always be a group of my Ummah fighting upon the truth, having the upper hand, not harmed by their opponents, until the decree of Allah (the Last Hour) comes.)
This Hadith was collected in the Sahih and narrated from `Abdullah bin `Amr.
وَلَئِنِ اتَّبَعْتَ أَهْوَآءَهُم بَعْدَ الَّذِي جَآءَكَ مِنَ الْعِلْمِ مَا لَكَ مِنَ اللَّهِ مِن وَلِيٍّ وَلاَ نَصِيرٍ
(And if you (O Muhammad ) were to follow their (Jews and Christians) desires after what you have received of Knowledge (i.e. the Qur'an), then you would have against Allah neither any Wali (protector or guardian) nor any helper.)
This Ayah carries a stern warning for the Muslim Ummah against imitating the ways and methods of the Jews and Christians, after they have acquired knowledge of the Qur'an and Sunnah, may Allah grant us refuge from this behavior. Although the speech in this Ayah was directed at the Messenger , the ruling of which applies to his entire Ummah.
The Meaning of Correct Tilawah
Allah said,
الَّذِينَ آتَيْنَـهُمُ الْكِتَـبَ يَتْلُونَهُ حَقَّ تِلاَوَتِهِ
(Those to whom We gave the Book. Yatlunahu Haqqan Tilawatih.)
`Abdur-Razzaq said from Ma`mar, from Qatadah, "They are the Jews and Christians." This is the opinion of `Abdur-Rahman bin Zayd bin Aslam, and it was also chosen by Ibn Jarir. Sa`id reported from Qatadah, "They are the Companions of the Messenger of Allah ﷺ." Abu Al-`Aliyah said that Ibn Mas`ud said, "By He in Whose Hand is my soul! The right Tilawah is allowing what it makes lawful, prohibiting what it makes unlawful, reciting it as it was revealed by Allah, not changing the words from their places, and not interpreting it with other than its actual interpretation." As-Suddi reported from Abu Malik from Ibn `Abbas who said about this Ayah (2:121): "They make lawful what it allows and they prohibit what it makes unlawful, and they do not alter its wordings." `Umar bin Al-Khattab said, "They are those who when they recite an Ayah that mentions mercy, they ask Allah for it, and when they recite an Ayah that mentions torment, they seek refuge with Allah from it." This meaning was attributed to the Prophet , for when he used to recite an Ayah of mercy, he invoked Allah for mercy, and when he recited an Ayah of torment, he sought refuge from it with Allah.
Allah's statement,
أُوْلَـئِكَ يُؤْمِنُونَ بِهِ
(they are the ones who believe therein)
explains the Ayah,
الَّذِينَ آتَيْنَـهُمُ الْكِتَـبَ يَتْلُونَهُ حَقَّ تِلاَوَتِهِ
(Those to whom We gave the Book. Yatlunahu Haqqa Tilawatihi).
These Ayat mean, "Those among the People of the Book who perfectly adhered to the Books that were revealed to the previous Prophets, will believe in what I have sent you with, O Muhammad!" Allah said in another Ayah,
وَلَوْ أَنَّهُمْ أَقَامُواْ التَّوْرَاةَ وَالإِنجِيلَ وَمَآ أُنزِلَ إِلَيهِمْ مِّن رَّبِّهِمْ لاّكَلُواْ مِن فَوْقِهِمْ وَمِن تَحْتِ أَرْجُلِهِم
(And if only they had acted according to the Tawrah, the Injil, and what has (now) been sent down to them from their Lord (the Qur'an), they would surely, have gotten provision from above them and from underneath their feet.) (5:66). The Ayah,
قُلْ يَـأَهْلَ الْكِتَـبِ لَسْتُمْ عَلَى شَىْءٍ حَتَّى تُقِيمُواْ التَّوْرَاةَ وَالإِنجِيلَ وَمَآ أُنزِلَ إِلَيْكُمْ مِّن رَّبِّكُمْ
(Say (O Muhammad ) "O People of the Scripture (Jews and Christians)! You have nothing (as regards guidance) till you act according to the Tawrah, the Injil, and what has (now) been sent down to you from your Lord (the Qur'an).") means, "If you adhere to the Torah and the Gospel in the correct manner, believe in them as you should, and believe in the news they carry about Muhammad's ﷺ prophethood, his description and the command to follow, aid and support him, then this will direct you to adhere to truth and righteousness in this life and the Hereafter." In another Ayah, Allah said,
الَّذِينَ يَتَّبِعُونَ الرَّسُولَ النَّبِىَّ الأُمِّىَّ الَّذِى يَجِدُونَهُ مَكْتُوبًا عِندَهُمْ فِى التَّوْرَاةِ وَالإِنجِيلِ
(Those who follow the Messenger, the Prophet who can neither read nor write (i.e. Muhammad ) whom they find written with them in the Tawrah and the Injil.) (7:157) and,
قُلْ ءَامِنُواْ بِهِ أَوْ لاَ تُؤْمِنُواْ إِنَّ الَّذِينَ أُوتُواْ الْعِلْمَ مِن قَبْلِهِ إِذَا يُتْلَى عَلَيْهِمْ يَخِرُّونَ لِلاٌّذْقَانِ سُجَّدًا - وَيَقُولُونَ سُبْحَانَ رَبِّنَآ إِن كَانَ وَعْدُ رَبِّنَا لَمَفْعُولاً
(Say (O Muhammad to them): "Believe in it (the Qur'an) or do not believe (in it). Verily, those who were given knowledge before it, when it is recited to them, fall down on their faces in humble prostration. And they say: "Glory be to our Lord! Truly, the promise of our Lord must be fulfilled.") (17:107-108).
These Ayat indicate that what Allah promised for Muhammad ﷺ will certainly occur. Allah also said,
الَّذِينَ ءَاتَيْنَـهُمُ الْكِتَـبَ مِن قَبْلِهِ هُم بِهِ يُؤْمِنُونَ - وَإِذَا يُتْلَى عَلَيْهِمْ قَالُواْ ءَامَنَّا بِهِ إِنَّهُ الْحَقُّ مِن رَّبِّنَآ إنَّا كُنَّا مِن قَبْلِهِ مُسْلِمِينَ - أُوْلَـئِكَ يُؤْتُونَ أَجْرَهُم مَّرَّتَيْنِ بِمَا صَبَرُواْ وَيَدْرَؤُنَ بِالْحَسَنَةِ السَّيِّئَةَ وَمِمَّا رَزَقْنَـهُمْ يُنفِقُونَ
(Those to whom We gave the Scripture (i. e. the Tawrah and the Injil) before it, they believe in it (the Qur'an). And when it is recited to them, they say: "We believe in it. Verily, it is the truth from our Lord. Indeed even before it we have been from those who submit themselves to Allah in Islam as Muslims. These will be given their reward twice over, because they are patient, and repel evil with good, and spend (in charity) out of what We have provided them.) (28:52-54) and,
وَقُلْ لِّلَّذِينَ أُوتُواْ الْكِتَـبَ وَالاٍّمِّيِّينَ ءَأَسْلَمْتُمْ فَإِنْ أَسْلَمُواْ فَقَدِ اهْتَدَواْ وَّإِن تَوَلَّوْاْ فَإِنَّمَا عَلَيْكَ الْبَلَـغُ وَاللَّهُ بَصِيرٌ بِالْعِبَادِ
(And say to those who were given the Scripture (Jews and Christians) and to those who are illiterates (Arab pagans): "Do you (also) submit yourselves (to Allah in Islam)" If they do, they are rightly guided; but if they turn away, your duty is only to convey the Message; and Allah is the Seer of (His) servants) (3:20).
Allah said,
وَمن يَكْفُرْ بِهِ فَأُوْلَـئِكَ هُمُ الْخَـسِرُونَ
(And whoever disbelieves in it (the Qur'an), those are they who are the losers), just as He said in another Ayah,
وَمَن يَكْفُرْ بِهِ مِنَ الاٌّحْزَابِ فَالنَّارُ مَوْعِدُهُ
(But those of the sects (Jews, Christians and all the other non-Muslim nations) that reject it (the Qur'an), the Fire will be their promised meeting place) (11:17).
As recorded in the Sahih, the Prophet said,
«وَالَّذِي نَفْسِي بِيَدِهِ لَا يَسْمَعُ بِي أَحَدٌ مِنْ هذِهِ الْأُمَّةِ يَهُودِيٌّ وَلَا نَصْرَانِيٌّ ثُمَّ لَا يُؤْمِنُ بِي إِلَّا دَخَلَ النَّار»
(By He in Whose Hand is my soul! There is no member of this Ummah (mankind and Jinns), Jew or a Christian, who hears of me, yet does not believe in me, but will enter the Fire.)