What is the virtue of seeking forgiveness (Istighfar)? And is its abundance a reason for the supplication (Du'a) to be answered? And did the Prophet, may Allah's prayers and peace be upon him, mention a specific number of daily Istighfar that is recommended to be recited, such as five hundred, a thousand, or two thousand, which are said to have great virtue?

Seeking forgiveness (Istighfar) is a great virtue. It was reported that the Prophet (peace be upon him) used to seek Allah's forgiveness and repent to Him more than seventy times a day, and in another narration, one hundred times. Among the forms of his supplication for forgiveness were: "I seek forgiveness from Allah, other than Whom there is no deity, the Ever-Living, the Sustainer, and I repent to Him," and "My Lord, forgive me and accept my repentance, for You are the Accepter of Repentance, the Forgiving." Increasing one's acts of seeking forgiveness opens doors to goodness and leads to the answering of prayers, as Allah Almighty said: {And said, 'Seek forgiveness of your Lord; indeed, He is ever Forgiving. (10) He will send [rain from] the sky upon you in [copious] showers (11) and give you increase in wealth and children and make for you gardens and make for you rivers.'} (Quran 71:10-12). And the Prophet (peace be upon him) said: "Whoever adheres to seeking forgiveness, Allah will make for him a way out of every worry, and from every difficulty an exit, and will provide for him from where he does not expect."