يَا أَيُّهَا الَّذِينَ آمَنُوا لَا تَتَّخِذُوا بِطَانَةً مِّن دُونِكُمْ لَا يَأْلُونَكُمْ خَبَالًا وَدُّوا مَا عَنِتُّمْ قَدْ بَدَتِ الْبَغْضَاءُ مِنْ أَفْوَاهِهِمْ وَمَا تُخْفِي صُدُورُهُمْ أَكْبَرُ ۚ قَدْ بَيَّنَّا لَكُمُ الْآيَاتِ ۖ إِن كُنتُمْ تَعْقِلُونَ (118)
(3:118) Believers! Do not take for intimate friends those who are not of your kind. They spare no effort to injure you. *92 Indeed they love all that distresses you. Their hatred is clearly manifest in what they say, and what their breasts conceal is even greater. Now We have made Our messages clear to you, if only you can understand (the danger of their intimacy).
*92). The Jews living on the outskirts of Madina had long enjoyed friendly relations with the two tribes of Aws and Khazraj. In the first place this was the result of relations between individuals. Later, they were bound by ties of neighbourliness and allegiance as a result of tribal inter-relationship. Even after the people of Aws and Khazraj embraced Islam, they maintained their old ties with the Jews and continued to treat them with the same warmth and cordiality. However, the hostility of the Jews towards the Arabian Prophet (peace be on him) and towards his mission was far too intense to allow them to maintain a cordial relationship with anyone who had joined the new movement. Outwardly, the Jews maintained the same terms of friendship with the Ansar (Helpers) as before but at heart they had become their sworn enemies. They made the best use of this pretended friendship, and remained constantly on the look-out for opportunities to create schisms and dissensions in the Muslim body-politic, and to draw out the secrets of the Muslims and pass them on to their enemies. Here God warns the Muslims to note this hypocrisy and take the necessary precaution.