punishment for sins can be removedby around ten causes-Ibn Taymiyyah

Shaykh al-Islaam Ibn Taymiyyah (rahimahullaah) stated as occurs in Majmu' al-Fatawa (7/487):

دلت نصوص الكتاب والسنة على أن عقوبة الذنوب تزول عن العبد بنحو عشرة أسباب : أحدها : التوبة ، وهذا متفق عليه بين المسلمين ، السبب الثاني : الاستغفــار ، السبب الثالث : الحسنات الماحية السبب الرابع : الدافـع للعقاب ، دعاء المؤمنين للمؤمن مثل صلاتهم على جنازته ، السبب الخامس : ما يعمل للميت من أعمال البر ، كالصدقة ونحوها ، السبب السادس : شفاعـة النبي (صلى الله عليه وسلم) وغيره في أهل الذنـوب يوم القيامة ، السبب السابع : المصائب التي يكفر الله بها الخطايا في الدنيا ، السبب الثامن : ما يحصل في القبر من الفتنة والضغطة والروعة ، السبب التاسع : أهوال يوم القيامة وكربها وشدائدها ، السبب العاشر : رحمة الله وعفوه ومغفرته بلا سبب من العباد

The texts of the Book and the Sunnah have indicated that the punishment (due) for sins can be removed from the servant by around ten causes. The first: Repentance, and this is agreed upon amongst the Muslims. The second cause: Seeking forgiveness. The third cause: Good deeds which wipe out (evil deeds). The fourth cause: That which repels punishment, the supplication of the believers for a believer, such as praying over his funeral. The fifth cause: What is done for the dead of righteous deeds such as charity and its likes. The sixth cause: The intercession of the Prophet (sallallaahu alayhi wasallam) and others for the sinners on the Day of Judgement. The seventh cause: Calamities by which Allaah expiates sins in the life of this world. The eighth cause: What occurs in the grave of tribulation, compression and fear. The ninth cause: The terrors of the Day of Judgement and the severity of its hardships. The tenth: The mercy of Allaah, His pardon and forgiveness without any reason (necessitating that) from the servant.

Comment

Note that three affairs come from a servant himself (repentance, seeking forgiveness, good deeds). Three affairs come from other than the servant (supplication, deeds of others which reach the dead and intercession). And three affairs are from the calamities (of life, the barzakh and the day of judgement) that expiate the sins. And after these nine matters, there is left but the pure mercy of Allaah, the Mighty and Majestic. In this is a refutation of the Kharijites who hold a person who dies with major sins (not having repented) is a disbeliever in the Fire forever, since expiation of sins can take place through other than repentance and seeking forgiveness, and exhausting those other means (which come from other than the servant himself), there still remains the pure mercy of Allaah, the Exalted. And this in itself indicates the great mercy of Allaah, the Sublime and Exalted in that He did not restrict and limit the causes of forgiveness to the servant himself.