“Indeed, the righteous will surely be in bliss, and indeed, the wicked will surely be in a blazing Fire.” (82:13-14)

For this very reason some of the shaykhs, when they instructed their followers to repent but feared that their hearts might recoil or grow weary, would simply command them to be truthful. Accordingly, the words of the spiritual masters and leading imams of the religion abound with talk of truthfulness and sincerity; they even say, “Tell anyone who does not speak the truth: do not follow me.” They also say, “Truthfulness is the sword of Allah on earth—whenever it is laid upon something, it cuts through it.”
Yūsuf ibn Asbāṭ and others used to say, “No servant is ever true with Allah without Allah then acting on his behalf.” Similar sayings are many.

Truthfulness and sincerity are the very realisation of faith and Islam, for those who outwardly profess Islam fall into two categories: believer and hypocrite. The line of demarcation between the believer and the hypocrite is truthfulness, as in His statement in Sūrat al-Ḥujurāt (49:14-15): “The Bedouins say, ‘We believe.’ Say: ‘You have not believed; rather say, ‘We have submitted’ … The believers are only those who believe in Allah and His Messenger, then harbor no doubt, and strive with their wealth and their lives in the way of Allah; those are the truthful.’”

Likewise, He says in Sūrat al-Ḥashr (59:8): “It is for the poor emigrants who were driven from their homes and their possessions, seeking bounty from Allah and His pleasure, and supporting Allah and His Messenger—those are the truthful.” Thus He informed that the truthful in their claim to faith are the believers whose belief is unmarred by doubt and who strive in His path with their wealth and their selves.

This is because such faithfulness is the covenant taken from both the first and the last of peoples, as the Exalted says in Sūrat Āl ʿImrān (3:81): “And [remember] when Allah took the covenant with the prophets: ‘Whatever I give you of Scripture and wisdom, then a Messenger comes to you confirming what is with you—you must believe in him and support him.’ He said, ‘Do you affirm and take upon that My commitment…’” Ibn ʿAbbās (d. 68 AH) said: “Allah never sent a prophet without first taking from him the covenant that if Muhammad were sent during his lifetime he would believe in him and support him, and that he should take the same covenant from his community: that they would believe in him and support him.”

The Exalted has also said in Sūrat al-Ḥadīd (57:25): “We certainly sent Our messengers with clear proofs and sent down with them the Book and the balance so that people might uphold justice; and We sent down iron, in which is severe might and benefits for mankind, so that Allah may know who will support Him and His messengers unseen. Truly, Allah is All-Strong, Almighty.” Here He mentions that He sent down the Book and the balance, and that He sent down iron, all for the establishment of justice and so that Allah may know who supports Him and His messengers.

For this reason the religion stands upon a Book that guides and a sword that grants victory—“and your Lord suffices as a Guide and a Supporter.” The Book and iron, although both are described as “sent down,” need not have been sent down from the same place: one may have descended from where the other did not. The Book, for example, is sent down from Allah, as He says at the beginning of Sūrat al-Zumar: “The revelation of the Book is from Allah, the Almighty, the Wise,” and at the beginning of Sūrat Hūd: “A Book whose verses are perfected and then set out in detail from One Wise, All-Aware,” and in Sūrat al-Naml: “You indeed receive the Qur’an from One Wise, All-Knowing.” Iron, on the other hand, is sent down from the mountains that He creates within them.

In the same way, He described the truthful in their claim to righteousness—which is the comprehensive essence of the religion—in His saying in Sūrat al-Baqarah: “Righteousness is not that you turn…"