Muslims are sincere people who devote their lives to earn Allah's good pleasure, in hope of attaining Paradise. This goal instills them with vitality and zealousness and keeps them vividly alert throughout their lives. No matter what conditions they find themselves in, their zeal never abates; they are continually sincere and submissive towards Allah, and scrupulously observe Allah's commands and prohibitions. One who sincerely believes in Allah believes with all certainty that each of the myriad of systems in the universe is under Allah's control, and that He creates ease after each hardship. This fact is related in the Qur'an as follows:
For truly with hardship comes ease; truly with hardship comes ease. (Surat al-Inshirah, 5-6)
… Allah does not demand from any self more than He has given it. Allah will appoint after difficulty, ease. (Surat at-Talaq, 7)
Muslims believe with certainty that Allah's promise is true. They remain conscious that every aspect of that which happens is pre-determined according to a plan and purpose, and thus is to lead to some ultimate good. This is the sort of faith unique to people who believe in Allah with certainty, and know that the Qur'an is the true revelation. As a result of this conviction, Muslims remain energetic and eager. As Allah informs us in the Qur'an, they "compete in doing good."
Race each other to forgiveness from your Lord and a Garden as wide as the heavens and the earth, prepared for those who do their duty. (Surah Al 'Imran, 133)
You who believe, be steadfast; be supreme in steadfastness; hold yourselves ready; and heed Allah; so that hopefully you will be successful. (Surah Al 'Imran, 200)
They believe in Allah and the Last Day, and enjoin the right and forbid the wrong, and compete in doing good. They are among the righteous. (Surah Al 'Imran, 114)
True Muslims are distinguished from others by their zeal and enthusiasm for earning Allah's good pleasure and adopting moral perfection. But, what some who call themselves "Muslims" say, and what they actually harbor in their hearts, may differ greatly. One who claims to be a Muslim may in actually be of poor faith; furthermore, at some future time, he may develop serious doubts about the existence of Allah and the Hereafter. In Surat al-Hajj, verse 53, Allah informs us of these people as "those whose hearts are hard" and "those with sickness in their hearts." In spite of their bearing witness to Allah's signs, they fail to show even the faintest desire to achieve sincere zeal or to attain moral perfection. Still, they may pretend to experience the qualities of Islam by imitating Muslims.
While, on the one hand, they aim to present themselves as true Muslims, they may, otherwise, attempt to impart their misguided opinions to the true Muslims. They aim to promote as acceptable a manner of life distant from the religion; they may also, through various means, endeavor to lead the believers astray. However, no matter what they scheme, they cannot damage Allah's religion, harm His sincere servants, or deviate them from the right path. In due time, Allah will make known the sickness that was in their hearts:
Or did those with sickness in their hearts imagine that Allah would not expose their malevolence? (Surah Muhammad, 29)
These people, who scheme secretly to bring about passivity and idleness among the believers, will never accomplish their goals. In any case, when they finally make known their real intentions, the Muslims are not taken by surprise, for, by Allah's will, long before they had revealed their insincerity, out of insight and wisdom, the Muslims would have recognized their poor faith and the sickness in their hearts. Their passivity never affected them; on the contrary, they admonish them, in the light of the verses. In compliance with the command of the Qur'an, "Allah knows what is in such people's hearts so turn away from them and warn them and speak to them with words that take effect" (Surat an-Nisa', 63), they talk to these people in an influential manner.
However, despite the good intentions and best efforts of the Muslims, most of these people continue in their unbelief. Allah informs us about the condition of these people as follows:
Who could do greater wrong than someone who is reminded of the Signs of his Lord and then turns away from them, forgetting all that he has done before? We have placed covers on their hearts, preventing them from understanding it, and heaviness in their ears. Though you call them to guidance, they will nonetheless never be guided. (Surat al-Kahf, 57)
It is incumbent upon the sincere believers to alert others to this serious threat. In one verse, Allah says, "… Do not let those who have no certainty shake your firmness." (Surat ar-Rum, 60) For this reason, Muslims must refrain from passivity and all acts that give such an impression, and warn those who encourage others to adopt such reprehensible disposition. For Allah informs us that the end of those who strive in preventing others from living by the values of the Qur'an is as follows:
But people who strive against Our Signs, trying to nullify them, such people will be summoned to the punishment. (Surah Saba', 38)
But as for those who strive against My Signs and try to thwart them, they will be the Companions of the Blazing Fire. (Surat al-Hajj, 51)