We are but sinners, every believer sins and the best of the believers are the ones who repent. Repenting or seeking forgiveness of Allah Almighty is the goal of every Muslim. Repenting is an act of worship. It is one thing that Prophet Muhammad(peace be upon him) had told his ummah to do most of all and continually. The prophet Muhammad Peace be upon him had told us to repent many times a day, every day. He(peace be upon him) has taught us how to seek forgiveness from Allah, Almighty for all our sins.
Shaddad bin Aus (May Allah be pleased with him) said:
the Prophet Muhammad Peace and Blessings of Allah be upon him said
"The best supplication for seeking forgiveness (Syed-ul- Istighfar) is to say: 'Allahumma Anta Rabbi, la ilaha illa Anta, khalaqtani wa ana 'abduka, wa ana 'ala 'ahdika wa wa'dika mastata'tu, a'udhu bika min sharri ma sana'tu, abu'u laka bini'matika 'alayya, wa abu'u bidhanbi faghfir li, fa innahu la yaghfirudh-dhunuba illa Anta.
(O Allah! You are my Rabb. There is no true god except you. You have created me, and I am your slave, and I hold to Your Covenant as far as I can. I seek refuge in you from the evil of what I have done. I acknowledge the favors that you have bestowed upon me, and I confess my sins. Pardon me, for none but you have the power to pardon).'
He who supplicates in these terms during the day with firm belief in it and dies on the same day (before the evening), he will be one of the dwellers of Jannah; and if anyone supplicates in these terms during the night with firm belief in it and dies before the morning, he will be one of the dwellers of Jannah (Al-Bukari)
Memorize this simple dua and be the dweller of Paradise. This manner of seeking forgiveness shows us the glory of Allah aza-wajal. It refers to how week a human being is, and how much great Allah taa’la is. It refers that man is nothing in front of Allah. It refers the power of Tawheed (Believe in the oneness of Allah). The Prophet Muhammad (pace be upon him) said that whoever recites this dua with a firm belief in what he says will be the dweller of Jannah. Here all Allah is asking us to supplicate and repent with the belief that He is listening and He will grant us what we are seeking. We have to understand the meaning of this great manner of Istighfar and recognize the consequence of saying it. Saying this supplication with great belief will be a cause to enter paradise.
Consequently, we have to motivate ourselves to frequently say it on a regular basis, encourage our family members, our friends, and all Muslims to utter this Istighfar for seeking forgiveness from Allah the Almighty. Allah the Almighty is the most Generous accepts Istighfar from those who repent and return to their Creator.
And Allah knows best.