“Peace be upon you for your patient perseverance. How excellent is the ultimate abode! But those who break Allah’s covenant after it has been confirmed, sever what Allah has commanded to be joined, and spread corruption on earth—it is they who will be cursed, and theirs will be the wretched abode.” [al-Ra'd: 24–25] [al-Ra'd]
He also said:
“Is it not the case that every time they make a covenant, a group of them casts it aside? Indeed, most of them do not believe.” [al-Baqara: 100] [al-Baqara]
And He said:
“Rather, true righteousness is that of those who believe in Allah, the Last Day, the angels, the Book, and the prophets; who give wealth—despite their love for it—to relatives, orphans, the needy, stranded travellers, beggars, and for freeing those in bondage; who establish prayer and give zakat; who fulfil their covenant when they make one; and who remain patient in poverty, hardship, and the heat of battle. It is they who have proven true, and it is they who are the God-fearing.” [al-Baqara: 177] [al-Baqara: 177]
Allah Most High also said:
“Among the People of the Book are those who, if entrusted with a fortune, will return it to you; and among them are those who, if entrusted with a single dinar, will not return it to you unless you persistently demand it. That is because they say, ‘We bear no liability concerning the unlettered,’ and knowingly tell lies about Allah. Indeed, whoever fulfils his covenant and fears Allah—surely Allah loves the God-fearing.” [Āl Imrān: 75–76] [Āl Imrān]
And He said:
“Indeed, those who exchange Allah’s covenant and their oaths for a paltry gain will have no share in the Hereafter. Allah will neither speak to them nor look upon them on the Day of Resurrection, nor will He purify them; and they will suffer a painful punishment.” [Āl Imrān: 77] [Āl Imrān]
Allah Most High also said:
“That is the expiation for your oaths when you have sworn them. And guard your oaths. Thus does Allah make His signs clear to you, so that you may be grateful.” [al-Mā'ida: 89] [al-Mā'ida: 89]
The hadiths concerning this are numerous. Among them is the report in the two Sahih collections from Abdullah ibn Umar, who said that the Messenger of Allah—may Allah bless him and grant him peace—said: “There are four traits which, if all are found in a person, make him a complete hypocrite. Whoever possesses one of them possesses a trait of hypocrisy until he abandons it: when he speaks, he lies; when he promises, he breaks his promise; when he enters into a covenant, he acts treacherously; and when he disputes, he transgresses all bounds.”
Also in the two Sahih collections, Abdullah ibn Umar reported that the Messenger of Allah—may Allah bless him and grant him peace—said: