الجواب وباللہ التوفیق

Both of these words are used in the meaning of “to forgive” and “forgiveness”. But Imam Razi R.A. has stated the difference between مغفرت and عفو that مغفرت is to cover the sins and عفو is to erase the sins (تفسیر رازی : ۳۴۹ و ۳۴۰ ), i.e., in عفوAllaah Ta’alaa erases the sins from the Book of Deeds, from the  Kiraaman Kaatibeen, and from the minds of the slaves so the slave would never feel ashamed remembering his sin. (الجامع فی اسماء اللہ تعالیٰ لابن قیم و القرطبی وابن کثیر: ۲۰۴)

Imam Raghib Isfahani R.A. says that عفو is to abandon the accountability and مغفرت is to hide the sins. (مفردات القران : ۱؍۶۰۰)

Hafiz Ibne Kathir R.A. says that عفو is to forgive the mistakes and errors between Allaah Ta’alaa and slave and مغفرت is to hide the mistakes from the slaves. (تفسیر ابن کثیر۱؍۷۳۸)

واللہ اعلم بالصواب