Be it known to you that in addition to the months of Sha’ban and Ramaḍān, the month of Rajab enjoys a great honor, as cited in many narrations that have also conveyed the merits of this month. Furthermore, the Holy Prophet (ﷺ) is reported as saying,
Verily, Rajab is the Great Month of Allah. No other month can be as sacredand virtuous as this month. To fight against the polytheists during this month is forbidden. Most certainly, Rajab is the month of Allah, Sha’ban is my month, and Ramaḍān is the month of my people. Therefore, if one observes fasting on one day of this month, he will bindingly win the Grand Pleasure of Almighty Allah, will be taken away from His ire, and the gates of Hellfire will be closed in his face.
Imam Musa ibn Ja’far al-Kadhim (عليه السلام) is also reported to have said,
If one observes fasting on one day in Rajab, Hellfire will go away from him a distance of one year walking. One who fasts three days will bindingly win Paradise.
The Imam (عليه السلام) is also reported as saying,
Rajab is (the name of) a river in Paradise that is whiter than milk and sweeter than honey. Hence, if one fasts even a single day in Rajab, Almighty Allah will allow him to drink from that river.
Imam Ja’far al-Sadiq (عليه السلام) has reported the Holy Prophet (ﷺ) as saying:
Rajab is the month of imploring for forgiveness for my people; so, you should implore forgiveness repeatedly in this month much more than you do in other months, for Almighty Allah is forgiving and merciful. This month is described as the advantageous month, because mercy is poured on my people during it so heavily. You should thus repeat frequently the following imploration prayer:
“No, I have not,” answered I.
“You have missed great reward,” said the Imam (عليه السلام).
Such a great reward that none can ever grant except Almighty Allah. Verily, this month has been given precedence to the other months by Almighty Allah Who has also given its sanctity a great consideration and will have certainly honored those who observe fasting during it.
I then said, “O son of Allah’s Messenger, what if I fast on the rest days of Rajab, will I then be awarded anything of the rewards dedicated to those fasting in it?”
Imam al-Sadiq (عليه السلام) answered,
Listen, Salim! If one observes fasting on the last day of this month, this will secure him against the agonies of death, the horror of the resurrection, and the grave chastisement. As for one who observes fasting on the last two days of this month, this will give him permission to pass the Discriminating Bridge (sirat) peacefully. As for one who observes fasting on the last three days of the month, one shall be secured on the Grand Horror Day against all the horrors and hardships thereon and shall be also granted release from Hellfire.
Finally, be it known to you that to observe fasting during the month of Rajab wholly brings about great favours. However, it has been narrated that one who is incapable of fasting during the month of Rajab may repeat the following supplicatory prayer instead one hundred times each day in Rajab: