What does Allah عَزَّوَجَلَّ’s grace and mercy mean?

What does Allah’s عَزَّوَجَلَّ grace and mercy mean in this blessed Ayah? Exegetists have stated different opinions about it. Sayyiduna Abdullah Bin Abbas رَضِىَ اللهُ تَعَالٰی عَـنْهُمَا, Sayyiduna Hassan and Sayyiduna Qattada رَضِىَ اللهُ تَعَالٰی عَـنْهُمَا have said that the meaning of Allah‘s عَزَّوَجَلَّ grace is Islam and His mercy means the Holy Quran. At another place it is stated that Allah’s عَزَّوَجَلَّ grace refers to the Holy Quran and His mercy refers to Ahadees. Whereas some Islamic scholars have stated that Allah’s عَزَّوَجَلَّ grace is the Beloved Rasool صَلَّى اللهُ تَعَالٰى عَلَيْهِ وَاٰلِهٖ وَسَلَّم and His mercy is the Holy Quran. Allah عَزَّوَجَلَّ has stated: 

وَ كَانَ فَضْلُ اللّٰهِ عَلَیْكَ عَظِیْمًا(۱۱۳)

and upon you is Allah’s great munificence

[Translation of Quran (Kanz-ul-Iman)](Part. 5, Surah An-Nisa, Ayah 113)

Some have stated: The grace of Allah عَزَّوَجَلَّ is Quran and mercy is the Beloved Rasool صَلَّى اللهُ تَعَالٰى عَلَيْهِ وَاٰلِهٖ وَسَلَّم. As Allah عَزَّوَجَلَّ has stated:

وَ مَاۤ اَرْسَلْنٰكَ اِلَّا رَحْمَةً لِّلْعٰلَمِیْنَ(۱۰۷)

And We did not send you except as a mercy for the entire world

[Translation of Quran (Kanz-ul-Iman)](Part. 17, Surah An-Anbiya, Ayah 107)

And if, for instance, in this blessed Ayah, grace and mercy do not especially refer to the Beloved Rasool صَلَّى اللهُ تَعَالٰى عَلَيْهِ وَاٰلِهٖ وَسَلَّم, then it is stated separately that the Beloved Rasool صَلَّى اللهُ تَعَالٰى عَلَيْهِ وَاٰلِهٖ وَسَلَّم is certainly the greatest grace and mercy of Allah عَزَّوَجَلَّ. Therefore one should feel happy about the blessed personality of the Beloved Rasool صَلَّى اللهُ تَعَالٰى عَلَيْهِ وَاٰلِهٖ وَسَلَّم either by holding a Milaad gathering or celebrating blessed Mai’raj. However, if someone does not feel delight or rejoice on this occasion, he is unfortunate and he is different from us, so he should think about his faith. (Sirat-ul-Jinaan, vol. 4, pp. 340)