Narrated 'Abdur-Rahman bin Ka'b bin Malik:
from his father who said: I did not remain behind from any of the battles the Prophet (ﷺ) fought in, until the battle of Tabuk, except for Badr. And the Prophet (ﷺ) did not scold anyone who remained behind from Badr, because he only went out to look for the caravan. The Quraish came out to help their caravan, so they met without an appointment as Allah the Mighty and Sublime, said. By my life, people consider the most honorable of battles of the Messenger of Allah (ﷺ) to be that of Badr, but I would not have liked to attend it instead of my oath of allegiance on the night of Al-'Aqabah when we took a covenant for Islam. Afterwards, I did not stay behind from the Prophet (ﷺ) until the battle of Tabuk, and it was the last of the battles he fought. The Messenger of Allah (ﷺ) informed the people of the departure - and he mentioned the Hadith in its entirety, and said - So I went to the Prophet (ﷺ) and he was sitting in the Masjid, surrounded by the Muslims. He was beaming like the moon beams. When he was happy about a matter he would beam. So I came and said in front of him. He said: 'Receive glad tidings - O Ka'b bin Malik - of the best day you have seen since your mother bore you!' So I said: 'O Prophet of Allah! Is it from Allah or from you?' He said: 'From Allah.' Then he recited these Ayat: Allah has forgiven the Prophet, the Muhajirin, and the Ansar who followed him in the time of distress, after the hearts of a party of them had nearly deviated, but He accepted their repentance. Certainly, He is unto them full of Kindness, Most Merciful (9:117). [until he reached: Verily, Allah is the One Who accepts repentance, Most Merciful (9:118).] He said: And it was about us that (the following) was revealed as well: Have Taqwa of Allah, and be with those who are true (9:119). He said: O Prophet of Allah! Part of my repentance is to not say but the truth, and give up all of my wealth as charity for Allah and His Messenger.' So the Prophet (ﷺ) said: 'Keep some of your wealth for yourself, for indeed that is better for you.' I said: 'So I will keep my share from Al-Khaibar.' He said: So after my acceptance of Islam, Allah did not grant me a greater favor than when I and my two companions told the truth to the Messenger of Allah (ﷺ) and we were not among the liars to be ruined like the others were ruined. Indeed I hope that Allah will not test anyone over telling the truth as he tested me. I did not resort to a lie ever since then, and I hope that Allah will protect me regarding what remains to come.