You have probably already read about this. This thread is to put into perspective the importance and power of this form of forgiveness.
Before you read about the master of all forms of forgiveness, consider the following form of seeking forgiveness.
أَسْتَغْفِرُ اللَّهَ الَّذِي لاَ إِلَهَ إِلاَّ هُوَ الْحَىُّ الْقَيُّومُ وَأَتُوبُ إِلَيْهِ
Narrated Zayd, the client of the Prophet:
The Prophet (sallallaahu alayhi wa sallam) said: If anyone says: "I ask pardon of Allah than Whom there is no deity, the Living, the eternal, and I turn to Him in repentance," he will be pardoned, even if he has fled in time of battle.
[Sunan Abi Dawud Hadith No. 1517]
To flee from the battlefield is a major sin. If you recite the above mentioned form of seeking forgiveness with sincerity
even that major sin is forgiven.
Keep in mind that the above mentioned form of seeking forgiveness was not labeled as the master of all form so forgiveness and yet it brings about such benefit.
Now imagine what the master of all forms of forgiveness can bring about?
اللَّهُمَّ أَنْتَ رَبِّي، لاَ إِلَهَ إِلاَّ أَنْتَ، خَلَقْتَنِي وَأَنَا عَبْدُكَ، وَأَنَا عَلَى عَهْدِكَ وَوَعْدِكَ مَا اسْتَطَعْتُ، أَعُوذُ بِكَ مِنْ شَرِّ مَا صَنَعْتُ، أَبُوءُ لَكَ بِنِعْمَتِكَ عَلَىَّ وَأَبُوءُ لَكَ بِذَنْبِي، فَاغْفِرْ لِي، فَإِنَّهُ لاَ يَغْفِرُ الذُّنُوبَ إِلاَّ أَنْتَ
Narrated Shaddad bin Aus:
The Prophet (sallallaahu alayhi wa sallam) said "The most superior way of asking for forgiveness from Allah is: '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 `alaiya, wa abu'u laka bidhanbi faghfir lee fa innahu la yaghfiru adhdhunuba illa anta." The Prophet (sallallaahu alayhi wa sallam) added. "If somebody recites it during the day with firm faith in it, and dies on the same day before the evening, he will be from the people of Paradise; and if somebody recites it at night with firm faith in it, and dies before the morning, he will be from the people of Paradise."
[Sahih al-Bukhari Hadith No. 6306]
Yes, that is the reward of this form of seeking forgiveness. If you recite it in the morning and die before the evening, you are guaranteed a place in Paradise.
And if you recite it in the evening and die before morning, you will be from the people of Paradise.
And remember you have to recite it with firm belief in it.
If there was not much you could do asides from the obligations laid upon you by Allaah and one more thing thing then it should be that
you memorize this, understand it, and recite it with firm belief once in the morning and once in the evening.
Allaah will, in shaa Allaah, bless you with the best in both worlds.