Allatheena AAahadta minhum thumma yanqudoona AAahdahum fee kulli marratin wahum la yattaqoon (surah Anfal: 56)

Tafseer Tafheem-ul-Quran by Syed Abu-al-A'la Maududi

(8:56) (especially) those with whom you entered into a covenant and then they broke their covenant time after time, and who do not fear Allah. *41

Allazeena`aahatta min hum summa yanqudoona `ahdahum fee kulli marratinw wa hum laa yattaqoon

*41). This refers especially to the Jews. After arriving in Madina, the Prophet (peace be on him) concluded a treaty of mutual co-operation and good neighbourliness with them. Not only did the Prophet (peace be on him) take the initiative in this connection, he also tried his best to maintain pleasant relations with them. The Prophet (peace be on him) also felt greater affinity with the Jews than with the polytheists of Makka. As a rule he always showed preference to the customs and practices of the People of the Book over those of the polytheists. But somehow the Jewish rabbis and scholars were irked by the Prophet's preaching of pure monotheism and moral uprightness, let alone his scathing criticism of the deviations which appeared in Jewish belief and conduct. They were constantly engaged, therefore, in efforts to sabotage the new religious movement. In this respect, theyleft no stone unturned. They collaborated with the hypocrites who were apparently an integral part of the Muslim body-politic. To serve the same end they fanned flames to rejuvenate the old animosities between the Aws and Khazraj which had brought about bloodshed and fratricide in pre-Islamic times. They attempted to hatch conspiracies against Islam in collaboration with the Quraysh and other tribes. What was all the more deplorable was that they indulged in these nefarious activities despite their treaty of friendship and co-operation with the Prophet (peace be on him).
When the Battle of Badr took place, they took it for granted that the Muslims would not be able to survive the very first attack of the Quraysh. However, when the outcome of the battle dashed their hopes, they became all the more spiteful. Apprehending that the victory in the Battle of Badr would help the Muslims consolidate their position, they carried out their hostile activities against Islam even more vigorously'. Ka'b b. Ashraf, a Jewish chief, went to Makka personally and recited stirring elegies for their dead warriors with a view to provoking the Quray'sh into hostile action against the Muslims. It was the same Ka'b b. Ashraf who considered the Muslim victory in the Battle of Badr such a catastrophe that he regarded death to be better than life. In his own words: 'The belly of the earth has become preferable to us than its back.' (Ibn Hisham, vol. 2. p. 51 - Ed.) Banu Qaynuqa', a Jewish tribe, in brazen violation of their agreement of friendship and alliance with the Muslims, took to indecent molestation and teasing the Muslim women who passed through their quarters. When the Prophet (peace be on him) reproached them for this shameful conduct, they threatened the Prophet (peace be on him), saying: 'Do not be deluded by your encounter with a people who had no knowledge of warfare, and so you had good luck with them. By God, if we were to wage war against you, you will know that we are the men.'(lbn Hisham, vol. 2, p. 47 - Ed.)