Asking Forgiveness

Pray Allah for forgiveness. Assuredly Allah is All-Forgiving, All-Compassionate. (an-Nisa 4:106)

Then glorify your Lord with His praise, and ask Him for forgiveness; for He surely is One Who returns repentance with liberal forgiveness and additional reward. (an-Nasr 110:3)

whoever does an evil or wrongs himself (by committing sins to harm himself spiritually), and then implores Allah for forgiveness, will find Allah All-Forgiving, All-Compassionate. (an-Nisa 4:110)

Allah would not punish them so long as you were among them; and Allah is not to punish them (or other people) while they implore Him for forgiveness for their sins. (al-Anfal 8:33)

They are also the ones who, when they have committed a shameful deed or wronged themselves (through any kind of sinful act), immediately remember Allah and implore Him to forgive their sins—for who will forgive sins save Allah?—and do not persist knowingly in whatever (evil) they have committed. (Al Imran 3:135)

867. Al-Agharr al-Muzani, may Allah be pleased with him, reported that the Messenger of Allah, peace and blessings be upon him, said, “A cloudiness comes over my heart and I ask for Allah’s forgiveness a hundred times a day.” (Sahih Muslim, Dhikr, 41).
Annotation: Although there is no evident report about what is meant by the heart’s being clouded, possible meanings can be as such:
The Prophet’s heart was constantly oriented toward Allah Almighty and when he had to carry out worldly responsibilities, he considered as a shadow over his relation with his Lord and thus asked forgiveness.
If he did not find an opportunity to make his habitual recitations, he would ask forgiveness owing to that delay.
When his heart was enveloped by sakinah (serenity), he asked forgiveness to offer worship and thanksgiving.
Scholars like Suyuti commented that this hadith is mutashabih (allegorical) and we cannot know what it exactly means; Allah knows best.

868. Abu Hurayra, may Allah be pleased with him, reported that the Messenger of Allah, peace and blessings be upon him, said, “By the One in whose hand my soul is, if you did not do wrong, Allah the Almighty would remove you and bring a people who do wrong and then ask Allah the Almighty for forgiveness and He would forgive them.” (Sahih Muslim, Tawbah, 11).

869. Ibn Umar, may Allah be pleased with him, said, “We used to count out for the Messenger of Allah, peace and blessings be upon him, in one assembly a hundred times, “Lord forgive me and turn to Me, You are the Tawwab (the One Who accepts repentance and returns it with liberal forgiveness and additional reward), the Merciful.” (Sunan Abu Dawud, Witr, 26; Sunan at-Tirmidhi, Da’awat, 39).

Nawawi, Imam. Riyad As-Salihin; The Gardens of the Righteous: A collection of authentic hadiths. Tughra Books Press, Inc. 2014