In The Name of Allaah, The Most Merciful, The Bestower of Mercy.
Shaddaad Bin Anas [radiyallaahu-anhu] said that the Prophet [sallal-laahu-alayhi-wasallam] said: The best way to seek the forgiveness of Allaah is to say: [اللَّهُمَّ أَنْتَ رَبِّي لَا إِلَهَ إِلَّا أَنْتَ خَلَقْتَنِي وَأَنَا عَبْدُكَ وَأَنَا عَلَى عَهْدِكَ وَوَعْدِكَ مَا اسْتَطَعْتُ أَعُوذُ بِكَ مِنْ شَرِّ مَا صَنَعْتُ أَبُوءُ لَكَ بِنِعْمَتِكَ عَلَيَّ وَأَبُوءُ لَكَ بِذَنْبِي فَاغْفِرْ لِي فَإِنَّهُ لَا يَغْفِرُ الذُّنُوبَ إِلَّا أَنْتَ – O Allaah! You are my Lord. There is no one who has the right to be worshipped except you. You created me and I am your slave, and I am [upon obedience and agreement] to my covenant and promise [to You] as much as I am able. I seek refuge with You from the evil I have done. I acknowledge in your presence all the blessings You have granted me, and I confess to You my sins. So forgive me, for indeed none is able to forgive [a slave his] sins, except You]. [Bukhaari Hadeeth Number 6306]
Reminders From This Supplication By Imaam Ibnul Qayyim [rahimahullaah]
[اللَّهُمَّ أَنْتَ رَبِّي – O Allaah! You are my Lord].
The suppliant affirms Tawheed Ar-Roboobiyyah which necessitates singling out Allaah [Glorified be He and free is He from all imperfections] as the Creator- the only One with All-Encompassing Will [i.e. whatever Allaah wills takes place and whatever He does not will cannot take place], All-Encompassing Authority [and control over everything].
[لا إِلَهَ إِلا أَنْتَ خَلَقْتَنِي وَأَنَا عَبْدُكَ – There is no one who has the right to be worshipped except you. You created me and I am your slave].
The suppliant affirms Tawheed Al-Ilaahiyyah, which necessitates having love for Allaah and worshipping Allaah alone without any partner; acknowledges his servitude to Allaah, which necessitates declaring his absolute poverty and need in the presence of Allaah -in all [affairs, situations, circumstances, instances].
Then suppliant says: [وَأَنَا عَلَى عَهْدِكَ وَوَعْدِكَ – And I am [upon obedience and agreement] to my covenant and promise (to You)].
This necessitates adherence to Allaah’s Sharee’ah, His command and the religion He has ordained, the covenant which He has enjoined on His servants; affirmation and belief in Allaah’s Promise, which is His recompense. So, this [part of the supplication conveys] adherence to Allaah’s command, affirming and belief in Allaah’s Promise which necessitates Eemaan and hoping for Allaah’s Reward. [However], the servants knows that he cannot fulfil this affair in the manner it truly deserves, so he mentioned his limited ability and power alongside it, saying: [مَا اسْتَطَعْتُ – as much as I am able]- Meaning: I adhere to it based on my limited ability and power. So, he testified to two affairs – [his limited] ability and power. Then he testified to his shortcomings, saying: [أَعُوذُ بِكَ مِنْ شَرِّ مَا صَنَعْتُ – I seek refuge with You from the evil I have done].
Then he testified that all blessings come from Allaah – Allaah is its owner, the One worthy of [being its owner, Bestower etc] and the One who brought it into existence prior to its non-existence], saying: [ أَبُوءُ لَكَ بِنِعْمَتِكَ عَلَيَّ وَأَبُوءُ لَكَ بِذَنْبِي– I acknowledge in your presence all the blessings You have granted me, and I confess to You my sins]- Meaning: You [O Allaah] are The One Who Deserves All Praise and Thanks- the One Who Deserves be to exolted, all good comes from You and all blessings are from You. You are the Owner of all praise, all exoltation belongs to You and all bounty is Yours; and I am the sinner, the one who commits wrong, acknowledges and accepts his mistake, just as has been stated by one of the Aarifeen [i.e. those who truly know their Lord] that, “The one who truly knows his Lord follows the path [i.e. the upright religion] through acknowledging and bearing witness to Allaah’s blessings as well as being well aware of the faults of his soul and the faults in his deeds”. So, acknowledging and bearing witness to Allaah’s blessings [or favours] necessitates that one loves his Lord [Glorified be He], praise and extol Him. And being well aware of the faults of one’s soul and deeds necessitates constant Istighfaar [i.e. seeking forgiveness], repentance, humility, obedience and submission.
Then after this is established in the heart of the suppliant and he seeks a means of approach to his Lord through these affairs [i.e. after affirming Allaa’s Ruboobiyyah and Uloohiyyah; affirming his servitude to Allaah, affirming that he has limited ability, acknowledges that all blessings belong to Allaah, accepting his faults, sin etc], he then says: [فَاغْفِرْ لِي فَإِنَّهُ لَا يَغْفِرُ الذُّنُوبَ إِلَّا أَنْت – So forgive me, for indeed none is able to forgive (a slave his) sins, except You]
An Excerpt from Tareequl Hijratayn pages 210-211. Slightly paraphrased