People always prefer easy ways. Cheating, especially in exams and the scientific field, spares a lot of time and effort. All that one needs is to lay his conscience to rest and enjoy the fruits of others’ toils and works. However, in the course of time a lot of people wake up conscience-stricken as they realize the falseness of all what others admire them for. This compunction turns their lives into hell, though it is a good sign that one’s heart is not completely dead. However, a question remains as to how to revoke what seems irrevocable?
AMJA Permanent Fatwa Committee stated: Cheating is one of the greatest sins and the ugliest customs. There is enough proof for the enormity of this sin in the saying of the Prophet (peace and blessings be upon him), “Whoever cheats is not of us.” This action takes a person out of the fold of faith (iman) [relegating him to the ranks of those Muslims who do not fulfil their basic obligations] because he has corrupted his religion and worldly affairs.
However, the door to repentance is wide open. It will not close until the sun rises from the west. We hope that the forgiveness and mercy of Allah will encompass you, if you have repented sincerely, by quitting this sinful act, regretting it and being firmly determined not to do the like of it again, ever.
As for what you have earned in terms of money, it is primarily halal, but it has been mixed with haram to the extent of the sin you fell into. You studied, learned and worked, but you took more than what you deserve. No one has a right to this money so that you may give it back to him, so it is yours. It has become lawful for you by your sincere repentance. (…So whosoever receives an admonition from his Lord and stops shall not be punished for the past; his case is for Allah (to judge) …) (Al-Baqarah 2:275)
As for the prayers and pilgrimage you have performed, we hope they would be accepted, since both of them are physical acts of worship and their acceptance has no relation to the permissible or prohibited nature of your wealth, according to the most correct opinion of the scholars. However, we would recommend that you repeat your Hajj with money that is halal, just to be on the safe side in terms of your religion and in order to avoid the difference in scholarly opinions, since some scholars have said that the pilgrimage is not accepted when it is performed with haram money.
If your scientific degrees—the legitimate and the illegitimate —are unrelated to your ability to treat patients, then there would be nothing wrong with continuing to do your job and to apply for full professorship whenever you are sure that you would be qualified to do so, and all of your research should henceforth be done with your own hands and the sweat of your brow. Do not inform anyone of what is in the past, for you should not scandalize yourself when Allah has covered up what you have done.
You must increase the amount you give in charity and the number of good deeds you do. (Verily, the good deeds remove the evil deeds (small sins). That is a reminder (some advice) for the mindful (those who accept advice).) (Hud 11:114) Perhaps Allah will overlook what has happened in the past and replace your bad deeds with good ones. Allah has promised whoever is sincere in repentance and who struggles in obedience after sinning, (Except those who repent and believe (in true Islamic monotheism), and do righteous deeds, for those, Allah will change their sins into good deeds, and Allah is Oft-Forgiving, Most Merciful.) (Al-Furqan 25:70) We hope you will be one of them