assalamu alaykum, if someone has committed several kinds of kufr or shirk, is it sufficient for him that he repents in a general way and then he speaks the shahada with the intention to re-enter islam? Or does he have to remember every kind of kufr or shirk which he has done? What's if he has repented in a general way and after that he remembered that he has committed one special deed of kufr or shirk? Was his repenting before that sufficient or does he have to repent again? Furthermore does he have to formulate sentences of repentence in his mind when he wants to re-enter islam?

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, we warn you against whispers about this matter because whispers are a door to much evil. Also, you should know that if a person had committed many sins and he forgot them, then a general repentance is enough for him whether it is polytheism or other sins of lesser degree of seriousness.

So, a Muslim should make a general repentance from all sins and he should be determined to remain steadfast on the Sharee’ah of Allaah The Almighty and not commit any sins again. This is enough a repentance for him and this is all that he can do as Allaah does not burden a soul beyond its power.

Then, if he remembers again some other sins, and he repents again from them, then this is good, otherwise he had already repented from them when he had made a general repentance from all his sins.

However, he is not obliged to say a certain formula for repentance, but whoever committed any form of disbelief, it is sufficient for him to utter the Two Testimonies of Faith, which is to say: "Ash-Hadu Allaa Ilaaha Illallaah Wa Ash-Hadu Anna Muhammadan Rasoolullaah" (I testify that none has the right to be worshipped but Allaah and I testify that Muhammad is the Messenger of Allaah), and to regret what he did and be determined not to do that again. For more benefit, please refer to Fatwa 86527.

Allaah Knows best.