On the authority of Anas b. Mālik (رضي الله عنه), “A man came to the Prophet (ﷺ) and said: ‘O Messenger of Allāh, which supplication is the best?’ He (ﷺ) said: ‘Ask Your Lord for pardon and well-being in this world and the Hereafter’. Then he came to him the next day and said: ‘O Prophet of Allāh, which supplication is the best?’ He (ﷺ) said: ‘Ask Your Lord for pardon (afwa) and well-being (aafiyah) in this world and the Hereafter, for if you are granted well-being in this life and in the Hereafter, then you have indeed succeeded.” (i.e to say

اللَّهُمَّ إِنِّي أَسْأَلُكَ الْعَفْوَ وَالْعَافِيَةَ فِي الدُّنْيَا وَالآخِرَةِ

Allahumma inni as’alukal-‘afwa wal-‘aafiyah(ta) fid-dunya wal-aakhirah

O Allah, I ask You for forgiveness and well-being in this world and in the Hereafter.

[Reported by Al-Bukhāri in Al-Adab Al-Mufrad (no. 637) and At-Tirmidhī (no. 3512). It was graded Sahīh by Al-Albānī in Sahīh Al-Adab Al-Mufrad (no. 495)] [Part of Morning& Evening Adhkar]
Abul-‘Āliyah [may Allāh bestow mercy upon him] said:

“The most abundant supplication I heard ‘Umar ibn al-Khattāb (رضي الله عنه) recite was:

اللَّهُمَّ عَافِنَا وَاعْفُ عَنَّا

Allāhumma ‘Aafinaa wa‘fu ‘Annaa

O’ Allāh, grant us well-being and pardon us.

[Collected by Al-Imām Ahmad in Kitāb az-Zuhd Page 617]

Abd-Abdallāh ibn ‘Umar (رضي الله عنه) said:

“Do not wish for death, for certainly you will die. Rather implore Allāh for well-being.”

[Collected by Al-Imām ibn Rajab al-Hambali in Latāif al-Ma’ārif Page 298] Translation: Authentic Quotes

Â’ishah (رضي الله عنها) said:

“If I knew which night was Laylatul-Qadr, I would not ask Allâh except for well-being in it.

[Narrated by ibn Abî Shaybah in al-Musannaf, ‘Abdul ‘Azîz al-Khudayr said the chain is authentic]

Mu’adh ibn Rifa’ah narrated from his father, who said that Abu Bakr (رضي الله عنه) stood upon the Minbar (pulpit), then he wept and said: “The Messenger of Allah (ﷺ) stood upon the Minbar the first year (of Hijrah), then he wept and said: ‘Ask Allah for pardon and Al-‘Aafiyah, for verily, none has been given anything better than Al-’Aafiyah after being granted Al-Yaqeen (certainty).”

[At-Tirmidhi no. 3558, and authenticated by Al-Albani who graded it Saheeh]