Istighfar

Istighfar is Arabic for “I seek forgiveness from Allah.” According to the Encyclopaedia of the Qur’an:

Istighfar is mentioned and recommended in the Quran more than 50 times. It is always present in the everyday language of Muslims and can express sorrow for anger, or used to persuade an angry person to calm down. Istighfar is mostly associated with the istiʿādha (invocation of God’s protection against Satan) (Nasr Hamid Abu Zayd, “Everyday Life, Qur’an In.” Encyclopaedia of the Qurʾān. General Editor: Jane Dammen McAuliffe [Leiden and Boston: Brill, 2005], CD-ROM version).

Quran 3:16 says of istighfar:

Istighfar, seeking forgiveness of Allah, is an important element in Islamic prayer (dua). Many Muslims believe the best dua for forgiveness is found in the hadith: ¹A hadith (plural ahadith) is an account of what Muhammad said or did, or of his tacit approval of something said or done in his presence (Encyclopaedia of Islam).

O Allah, You are my Lord. There is no god besides You. You created me and I am Your servant, following your covenant and [my] promise to you as much as I can. I seek refuge in You from the evil that I have done. Before You I acknowledge Your blessings bestowed upon me and I confess my sins to You. So forgive me, for surely no one can forgive sins except You.

The Prophet [صلى الله عليه وسلم] then added, ‘anyone who says this during the day, firmly believing in it, and dies before the evening; or says it in the evening, firmly believing in it, and dies before the following morning, will be among the people of paradise.’ ” (Sahih al-Bukhari, vol 8, pp.212-3, no 318)

Istighfar and God’s Justice

The Quran calls Allah:

The forgiving (al-ghāfir, Quran 7:155)
The oft-forgiver (al-ghafūr, Quran 2:173)
The all-forgiving (al-ghaffār, Quran 38:66; cf. 20:82)

The Quran also calls God just:

“the justest of judges” (ahkam al-hakimeen, Quran 11:45; 95:8).
“the best of judges” (khayru alhakimeena, Quran 7:87; 10:109; 12:80)
“The Holy,” “The Pure,” and “The Perfect” (Al-Quddus, Quran 59:23; 62:1).

How does istighfar fit with God being utterly just?

Is God’s pardon of great sin just?
Does God have to ignore some of His Names in order to show mercy to sinners?
Will the angels of heaven be able to look at forgiven sinners and also see objects of God’s perfect, holy, and just judgment?

How can God forgive and pardon sin while still maintaining His perfect justice?