Some may have feelings of sin and wrong doing even after repentance. Many feel anxiety because of what they have done in the past.
I have a feeling of guilt and regret. I am very anxious about my past. For example, I have committed a crime, a heinous crime, I have lied, I have cheated on someone. I have violated others rights.
This past could be dangerous.
Two nights ago, I was in some place, and a young man came to me, and said I have been a stealing for 4 years. I have repented, I have put my past aside, I am not a thief anymore. People have almost put their past aside. But I do not put my past aside. I messed up. Why? Because of this history of stealing. Someone has a past of drinking. And there are many types of sins. But… one must remember the Holy Quran has an answer for this.
قُلْ يَا عِبَادِيَ الَّذِينَ أَسْرَفُوا عَلَىٰ أَنفُسِهِمْ لَا تَقْنَطُوا مِن رَّحْمَةِ اللَّهِ
“Say, “O My servants who have transgressed against themselves [by sinning], do not despair of the mercy of Allah.” Az Zummar 53
Once a man said to the Imam a.s, “I am surprised that a person can find salvation with all this torment, with all this hell, with all this sin.” The Imam replied: That is a mistake. You should say, it is very strange, how could one be in torment with all the vastness of God’s mercy? It would be a surprise if one ends up being annihilated! God has put so many doors of entry to His mercy.
(وقيل له: يوما إن الحسن البصري قال: ليس العجب ممن هلك كيف هلك؟
وإنما العجب ممن نجا كيف نجا، فقال عليه السلام: أنا أقول: ليس العجب ممن نجا كيف نجا وأما العجب ممن هلك كيف هلك مع سعة رحمة الله.)
They said to Imam Kazim a.s, that someone does not fast on the month of Ramadan. He eats lunch during the day. They asked him, Why don’t you fast? He said I have committed many sins why should I bother? The Imam said, I fear the most of his despair, more so than I do not fear his sin.