Rajab Month

The Holy Prophet (pbuh)

منْ صَامَ مِنْ رَجَبٍ يَوْماً إِيمَاناً وَ اِحْتِسَاباً اِسْتَوْجَبَ رِضْوَانَ اَللَّهِ اَلْأَكْبَرَ وَ أَطْفَى صَوْمُهُ فِي ذَلِكَ اَلْيَوْمِ غَضَبَ اَللَّهِ عَزَّ وَ جَلَّ وَ أَغْلَقَ عَنْهُ بَاباً مِنْ أَبْوَابِ اَلنَّارِ

Be aware that anyone who fastes one day of the month of Rajab by faith and sincerity deserves great reward from Allah, and his fast on that day will undoubtedly turn off the anger of the Lord and a door of Hell would be closed for him

Bihar al-Anwar, v 94, p 26