ولا تجادلوا أهل الكتاب إلا بالتي هي أحسن إلا الذين ظلموا منهم (29:46) بالانجليزي

(29:46) Argue not *80 with the People of the Book except in the fairest manner, *81 unless it be those of them that are utterly unjust. *82 Say to them: 'We believe in what was revealed to us and what was revealed to you. One is our God and your God; and we are those who submit *83 ourselves to Him.'

Tafseer Abu-al-A'la Maududi

Page 402 English Traditional

*80) It should be noted that a little below in this Surah the people are being exhorted to migrate. At that time Habash was the only place of safety to which the Muslims could migrate, and Habash in those days was under the domination of the Christians. Therefore, in these verses the Muslims are being instructed as to how they should argue and discuss matters concerning religion with the people of the Book when such an occasion arises.
*81) That is, "The discussion should be conducted rationally, in a civilized and decent language, so that the ideas of the other person may be reformed. The preacher's chief aim should be to appeal to the addressee's heart, convey the truth to him and bring him to the right path. He should not fight like a wrestler whose only object is to defeat his opponent. He should rather conduct himself like a physician who is ever cautious not to cause the patient's ailment to worsen by any of his own mistakes, and tries to cure him with the least possible trouble. This instruction bas been given here especially in connection with the conduct of a discussion with the people of the Book, but is a general instruction pertaining to the preaching of the religion and it has been given at several places in the Qur'an. For example, "O Prophet, invite to the way of your Lord with wisdom and excellent admonition and discuss things with the people in the best manner." (AnNahl: 125). "O Prophet, goodness and evil are not alike. Repel evil with what is best. You will see that he. with whom you had enmity, has become your closest friend. ' (Ha Mim As-Sajdah: 34). "O Prophet, repel evil with what is best: We are fully aware of what they utter against you." (Al-Mu'minun: 96) "O Prophet, adopt the way of leniency and forbearance; enjoin what is good and avoid useless discussions with the ignorant people. If Satan ever excites you to anger, seek refuge in Allah."
*82) That is, "With those who adopt an attitude of wickedness a different attitude may also be adopted according to the nature and extent of their wickedness. In other words, one cannot, and should not adopt a soft and gentle attitude towards aII sorts of the people under aII circumstances at all time, which might be mistaken for the weakness and meekness of the inviter to the Truth. Islam does teach its followers to be polite, gentle and reasonable, but it does not teach them to be unduly humble and meek so that they are not taken for granted by every cruel and wicked person."
*83) In these sentences Allah Himself has provided guidance to the best method of discussion, which the inviters to the Truth should adopt. The method is this: "Do not make the error or deviation of the other person the basis and starting point of the discussion, but begin the discussion with those points of truth and justice which are common between you and your opponent. That is, the discussion should start' from the points of agreement and not from the points of difference. Then, arguing froth the agreed points, the addressee should be made to understand that, in the matter of the things in which you differ, your stand is in conformity with the agreed points whereas his stand is contradictory to them In this connection, one should bear in mind the fact that the people of the Book did not deny Revelation, Prophethood and Tauhid, like the polytheists of Arabia, but believed in these realities just tike the Muslims. After agreement on these basic things, the main thing that could become the basis of difference Between them could be that the Muslim would not believe in the Divine Scriptures sent down to them and would invite them to believe in the Divine Book sent down to themselves, and would declare them disbelievers if they did not believe in it. This would have been a strong basis of their conflict. But the Muslims had a different stand. They believed as true all those Books that were with the people of the Book, and then also had believed in the Revelation that had been sent down to the Holy Prophet Muhammad (Allah's peace be upon him). After this it was for the people of the Book to tell the rational ground for which they believed in one Book sent by Allah and rejected the other. That is why Allah here has instructed the Muslims that whenever they have to deal with the people of the Book, they should tirst of all present before them this very point of view in a positive manner. Say to them: "We believe in the same God in Whom you believe and we are obedient to Him. We have submitted ourselves to aII those Commands and injunctions and teachings that have come from Him, whether they were sent down to you, or to us. We are obedient servants of God and not of a country or a community or a race, that we should submit to God's Command when it is sent down in one place and reject it when it is sent down in another place. This thing has been repeated at several places in the Qur'an and particularly in relation to the people of the Book, it has been presented forcefully. For this,see AI-Baqarah: 4, 136, 177, 285; Al-i-`Imran: 84; An-Nisa': 136, 150 to 152, 162 to 164; AshShu'araa: 13.