All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger.
First of all, whoever repents from his sins even if it was Kufr [disbelief or an act that takes a person out of the fold of Islam], Allaah accepts his repentance and he becomes like a person who has never committed a sin, let alone other sins that are of a lesser degree than Kufr. Allaah Says (what means): {Say to those who have disbelieved [that] if they cease, what has previously occurred will be forgiven for them. But if they return [to hostility] —then the precedent of the former [rebellious] peoples has already taken place.} [Quran 8:38]
Moreover, Allaah may bestow His grace on whomever He wills and replaces his bad deeds with good deeds; as Allaah Says (what means): {Except for those who repent, believe and do righteous work. For them Allaah will replace their evil deeds with good. And ever is Allaah Forgiving and Merciful.} [Quran 25:70]
Besides, taunting a Muslim with a sin from which he had repented is something that is not permissible; it is feared that whoever does so, his heart is sick (deceitful) and that he likes to see people doing evil. Also, he may be included in the threat that is mentioned in the following verse; Allaah Says (what means): {Indeed, those who like that immorality should be spread [or publicized] among those who have believed will have a painful punishment in this world and the Hereafter. And Allaah knows and you do not know.} [Quran 24:19]
Likewise, it is not permissible to prevent a person from enjoining good and forbidding evil on the grounds that he used to do evil deeds in the past even if he had not repented from them, let alone if he had repented from them. Indeed, this is nothing but whispers of the devil and it has nothing to do with the religion of Islam.
Ibn Katheer said: “The correct opinion is that the scholar enjoins good even if he does not do it.” He provided much evidence for this statement among which are the following:
- The statement of Sa’eed Ibn Jubayr : “If a person does not enjoin good and does not forbid evil until he is free from sins, then no one would enjoin good or forbid evil.”
- Imaam Maalik said: “Ibn Jubayr has indeed told the truth; where is that person who is free from sins?”
On the other hand, it is not permissible to accuse a Muslim of hypocrisy as this is a very serious matter and this leads to many disadvantages. Indeed, if such a word comes out of the mouth of a person to another person, then such a word has to fall on one of them. The Prophet said: "Any person who says to his brother: 'O Kaafir (disbeliever)', so it falls back on one of them. If it is true, it is as he said, otherwise it returns back upon him (i.e. the one who said it)." [Al-Bukhari and Muslim]
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Moreover, it is a great calamity and it is a very serious matter that a Muslim interferes in a matter that belongs to Allaah regarding His forgiveness for His slaves, and says that Allaah will not forgive so and so, or that he makes him despair of the Mercy of Allaah. Jundub narrated that a man said: “I swear by Allaah that Allaah will not forgive so and so.” Then, the Prophet said: "Allaah said: “Who is this person who swears that I will not forgive so and so, indeed, I have forgiven so and so and I nullified your (own good) deeds.” [Muslim]
Furthermore, we wonder why that person is interested in Allaah's forgiving this person who repented from his sins or not forgiving him. Truly, he is more worthy of being reprimanded and disciplined for what he is doing, i.e. for taunting and defaming people, and for his improper conduct towards Allaah, Lord of the worlds.
Therefore, this man should be advised and reminded of Allaah and of Allaah’s severe punishment in this worldly life and the Hereafter if he persists on doing what he is doing. Allaah Says (what means): {And those who harm believing men and believing women for [something] other than what they have earned [i.e. deserved] have certainly born upon themselves a slander and manifest sin.} [Quran 33:58]
Moreover, the Prophet said: "O those who are Muslims by tongue whereas faith has not entered their hearts! Do not harm Muslims, or scoff at them or pursue their faults; for whoever pursue the imperfection of his Muslim brother, Allaah will pursue his imperfection, and whoever Allaah pursue his imperfection, He will disgrace him even if he hides himself in his own home." [Ibn Hibbaan who graded it as Saheeh (sound)]
Finally, that brother who is taunted by the other person should fear Allaah and be patient as Allaah does not cause the reward of those who do good to be lost, rather Allaah defends the believers. He should remember the saying of Allaah (which means): {And the servants of the Most Merciful are those who walk upon the earth easily, and when the ignorant address them [harshly] they say [words of] peace.}[Quran 25:63]
Allaah Knows best.