Reading through Islamic history we come to know that the Holy Prophet (Sallaho alaihe wasallam) pronounced Astagfirullah many a time during a day despite being pure of any sin. The companion of the Prophet (Sallaho alaihe wasallam) also did the same and asked the people to do so for the solution of their problems. Istaghfar has the following benefit:
Allaahumma ‘innee as’aluka fi’lal-khayraat wa tarkal-munkaraat wa hubbal-masaakeen wa an taghfara lee wa tarhamanee wa ithaa aradta fitnata qawmin
fatawaffanee ghayra maftoon, wa as’aluka hubbaka wa hubba man yuhibbuka
wa hubba ‘amalin yuqarribunee ilaa hubbik
O Allaah, I ask You to grant me the performance of good deeds, abandonment of bad ones, and love of the poor; and (I ask You) that You forgive me and have mercy upon me; and if You intend to try a people, cause me to die without being tested; and I ask You for Your love, and the love of those who love you, and the love of actions which draw me closer to Your love.
‘O my Lord forgive me and accept my repentance indeed You are the One who forgives and most merciful.’
“Our Lord! We have indeed believed, so forgive us our sins and save us from the punishment of the Fire.”
O Allaah You are my Lord, there is none worthy of worship in truth except You, You created me and I am Your slave and I am abiding to Your covenant and promise as best as I can, I seek refuge in You from the evil that I have committed, I profess to you my sins and I acknowledge Your favour upon me, so forgive me verily no one forgives sins except you.
Hazrat Hassan Basri (RA) was the great saint of Allah Almighty. He remained busy in the remembrance of Allah Almighty. Sometimes the people came to him for prayer (dua). It is the event told by a personrso who was present in the company of Hazrat Hassan Basri (RA) when he was delivering an Islamic lecture. While he was busy in his teaching a pen reached and asked him to pray for his prosperity. Hazrat Hassan Basri asked him to say Astaghfar abundantly. In the meantime, another person requested the saint to pray for him as he has no child. Hassan Basri (RA) once again said the same thing that he had said previously; he asked him to say Asftagfirullah abundantly. The person got satisfied.
Another person came and asked him to pray for his honor and dignity along with prosperity; the great saint of Allah Almighty gave the same piece of advice to him as he had given to the other person. On asking that he had said that same words for the solution of many problems; Hazrat Hassan Basri (RA) said that Astagfirullah is the powerful dua (Astaghfar prayer) for forgiveness. If you are forgiven by Allah Almighty; He restores his blessing upon you that have been prevented due to your mistakes. Allah never punishes you without any reason.