O you who believe! Say not (to the Messenger ﷺ) Ra'ina but say Unzurna (make us understand) and hear. And for the disbelievers there is a painful torment (104)Neither those who disbelieve among the People of the Scripture (Jews and Christians) nor Al-Mushrikin (the idolaters) like that there should be sent down unto you any good from your Lord. But Allah chooses for His mercy whom He wills. And Allah is the Owner of great bounty (105)
Manners in Speech
Allah forbade His believing servants from imitating the behavior and deeds of the disbelievers. The Jews used to use devious words that hide what they really meant. May Allah's curse be upon them. When they wanted to say, 'hear us,' they would use the word Ra'ina, which is an insult (in Hebrew, but means 'hear us' in Arabic). Allah said,
مِّنَ الَّذِينَ هَادُوا يُحَرِّفُونَ الْكَلِمَ عَن مَّوَاضِعِهِ وَيَقُولُونَ سَمِعْنَا وَعَصَيْنَا وَاسْمَعْ غَيْرَ مُسْمَعٍ وَرَاعِنَا لَيًّا بِأَلْسِنَتِهِمْ وَطَعْنًا فِي الدِّينِ وَلَوْ أَنَّهُمْ قَالُوا سَمِعْنَا وَأَطَعْنَا وَاسْمَعْ وَانظُرْنَا لَكَانَ خَيْرًا لَّهُمْ وَأَقْوَمَ وَلَٰكِن لَّعَنَهُمُ اللَّهُ بِكُفْرِهِمْ فَلَا يُؤْمِنُونَ إِلَّا قَلِيلًا
(Among those who are Jews, there are some who displace words from (their) right places and say: "We hear your word (O Muhammad ﷺ) and disobey," and "Hear and let you (O Muhammad ﷺ) hear nothing." And Ra'ina with a twist of their tongues and as a mockery of the religion (Islam). And if only they had said: "We hear and obey," and "Do make us understand," it would have been better for them, and more proper; but Allah cursed them for their disbelief, so they believe not except a few)(4:46).
Also, the Hadiths stated that when they would greet Muslims, they would say, 'As-Samu 'alaykum,' meaning, 'death be to you'. This is why we were commanded to answer them by saying, 'Wa 'alaykum,' meaning, 'and to you too', then our supplication against them shall be answered, rather than theirs against us.
Allah forbade the believers from imitating the disbelievers in tongue or deed. Allah said,
يَا أَيُّهَا الَّذِينَ آمَنُوا لَا تَقُولُوا رَاعِنَا وَقُولُوا انظُرْنَا وَاسْمَعُوا وَلِلْكَافِرِينَ عَذَابٌ أَلِيمٌ
(O you who believe! Say not (to the Messenger ﷺ) Ra'ina but say Unzurna (make us understand) and hear. And for the disbelievers there is a painful torment)(2:104).
Also, Imam Ahmad narrated that Ibn 'Umar said that the Messenger of Allah ﷺ said,
بُعِثْتُ بَيْنَ يَدَيِ السَّاعَةِ بِالسَّيْفِ حَتَّى يُعْبَدَ اللهُ وَحْدَهُ لَا شَرِيكَ لَهُ، وَجُعِلَ رِزْقِي تَحْتَ ظِلِّ رُمْحِي، وَجُعِلَتِ الذِّلَّةُ وَالصَّغَارُ عَلَى مَنْ خَالَفَ أَمْرِي، وَمَنْ تَشَبَّهَ بِقَومٍ فَهُوَ مِنْهُم
(I was sent with the sword just before the Last Hour, so that Allah is worshipped alone without partners. My sustenance was provided for me from under the shadow of my spear. Those who oppose my command were humiliated and made inferior, and whoever imitates a people, he is one of them.)
Abu Dawud narrated that the Prophet ﷺ said,
مَنْ تَشَبَّهَ بِقَوْمٍ فَهُوَ مِنْهُم
(Whoever imitates a people is one of them.)
These Hadiths indicate, along with their threats and warnings, that we are not allowed to imitate the disbelievers in their statements, deeds, clothes, feasts, acts of worship, etc., whatever actions of the disbelievers that were not legislated for us.
Ad-Dahhak said that Ibn 'Abbas commented on the Ayah,
لَا تَقُولُوا رَاعِنَا
(Say not (to the Messenger ﷺ) Ra'ina)
They used to say to the Prophet ﷺ, Ar'ina samak (which is an insult). Ibn Abu Hatim said that it was reported that Abu Al-'Aliyah, Abu Malik, Ar-Rabi' bin Anas, 'Atiyah Al-'Awfi and Qatadah said similarly. Further, Mujahid said, "Do not say Ra'ina' means, 'Do not dispute'." Mujahid said in another narration, "Do not say, 'We hear from you, and you hear from us.'" Also, 'Ata' said, "Do not say,
رَاعِنَا
(Ra'ina), which was a dialect that the Ansar used and which was forbidden from use by Allah."
Also, As-Suddi said, "Rifa'ah bin Zayd, a Jewish man from the tribe of Qaynuqa', used to come to the Prophet ﷺ and say to him, 'Hear, Ghayr Musma'in (let you hear nothing).' The Muslims used to think that the Prophets are greeted and honored with this type of speech, and this is why some of them used to say, 'Hear, let you hear nothing,' and so on, as mentioned in Surat An-Nisa." Thereafter, Allah forbade the believers from uttering the word Ra'ina." 'Abdur-Rahman bin Zayd bin Aslam also said similarly.
The extreme Enmity that the Disbelievers and the People of the Book have against Muslims
Allah said next (2:105),
مَّا يَوَدُّ الَّذِينَ كَفَرُوا مِنْ أَهْلِ الْكِتَابِ وَلَا الْمُشْرِكِينَ أَن يُنَزَّلَ عَلَيْكُم مِّنْ خَيْرٍ مِّن رَّبِّكُمْ
(Neither those who disbelieve among the People of the Scripture (Jews and Christians) nor Al-Mushrikin (the idolaters), like that there should be sent down unto you any good from your Lord).
Allah described the deep enmity that the disbelieving polytheists and People of the Scripture, whom Allah warned against imitating, have against the believers, so that Muslims should sever all friendship with them. Also, Allah mentioned what He granted the believers of the perfect Law that He legislated for their Prophet Muhammad ﷺ. Allah said,
وَاللَّهُ يَخْتَصُّ بِرَحْمَتِهِ مَن يَشَاءُ وَاللَّهُ ذُو الْفَضْلِ الْعَظِيمِ
(But Allah chooses for His mercy whom He wills. And Allah is the Owner of great bounty)(2:105).
Among other perversities, some of the Jews invented a new mischief. When they presented themselves before the Holy Prophet ﷺ they would address him with the word Ra` ina رَاعِنَا ، which, in Arabic, means "be mindful of us", but is, in Hebrew, a curse. The latter is what they intended, but the Arabs, not knowing Hebrew, could not see the point, and some Muslims too, with the Arabic sense of the word in mind, began to address the Holy Prophet ﷺ in the same manner to the great glee of the Jews who had thus found a way of insulting him openly, and had even tricked the Muslims into joining them. In order to frustrate the design of the Jews, the Holy Qur'an commands the Muslims to use the word Unzurna انظُرْنَا instead of Ra'ina رَاعِنَا ، for the meanings of the two words are the same in Arabic. The verse also announces a dire punishment to the Jews for showing disrespect to the Holy Prophet ﷺ and for trying to be clever with him.
The verse describes the insolent Jews as Kafirin کافرون (infidels), which means that being intentionally disrespectful towards a prophet even in an indirect manner constitutes infidelity.
The verse shows that if a perfectly legitimate action on one's part provides room for others to commit illegitimate actions, even the legitimate action no longer remains lawful for one. For example, if a permissible action on the part of a scholar is likely to lead the ignorant into error and to induce them to do impermissible things, that permissible action will then become forbidden for him, provided that the action concerned is not essential according to the Shari'ah and is not included among its objects. The Holy Qur'an and the Hadith provide many instances of this nature. For example, before the advent of Islam the Quraysh قریش had, in rebuilding the Ka'bah کعبہ ، made certain modifications in the design set by Sayyidna Ibrahim (Abraham علیہ السلام). A hadith reports that the Holy Prophet ﷺ wished to demolish the present structure, and to build it again according to the Abrahamic pattern, but he did not do so, for such an action could have led ignorant people into misunderstanding and error.
In the vocabulary of the Principles of Islamic Jurisprudence, such injunctions are described as سدَ الذرایع : Sadd al-Dhara'i: "removing the means (to error) " and are accepted by all the jurists -- those of the Hanbali school being very particular about them. (Qurtubi)