Blessings of the month of Rajjab

Heavenly River
Syedna Ans Ibn Maalik narrates that the Beloved Prophet of Almighty Allah said,

QUOTE :: Indeed there is a river in Heaven which is called Rajjab (?‘?Œ?ˆ). Its water is whiter than milk and sweeter than honey. Whoever keeps one Fast in the month of Rajjab, Allah will let him quench his thirst by drinking from that river.
(Shu'b-al-Iman, v3, p368, Hadith3800, Daar-al-Kutub-al-Ilmiyah, Beirut)


Five Blessings Nights
Syedna Abu Umama narrates that the Holy Prophet said,
QUOTE :: There are five nights in which supplications are not turned down:
1, The first night of Rajjab
2. Sha'baan's 15th night
3. The night between Thursday and Friday
4. The night before Eid-al-Fitr
5. The night before Eid-al-Adh'haa
(Jaame'-as-Sagheer, p241, Hadith3952, Daar-al-Kutub-al-Ilmiyah, Beirut)

Syedna Khalid bin Ma'daan says that,
QUOTE :: There are five particular nights in a whole year, that whosoever by testifying them spends these nights in worship with intention of gaining virtues , Almighty Allah will grant him entrance into Heaven:

The fisrt night of Rajjab, worships in the night and fasts during the day
Night before Eid-al-Fitr, worships in the night and but doesn't fast in the day
Night before Eid-al-Adh'haa, worships in the night and but doesn't fast in the day
Sha'baan 15th night, worships in the night and fasts during the day
Ashurah (Muharram 10th) night, worships in the night and fasts during the day
(Ghunya-tut-Talibeen, p236, Daar-al-Ihyaa-al-Thurath-al-Arabi, Beirut)

First Day Fasting of Rajjab is Penitence for 3-yrs of Sin

Syedna Abdullah Ibn Abbas narrates that the Holy Prophet said,
QUOTE :: The Fast of first day of Rajjab is penitence for 3 years, the fast of the second day is penitence for 2 years and the fast of the third day is penitence for 1 year and then, each fasting day of Rajjab is penitence for the 1 month.
(Jaame'-as-Sagheer, p311, Hadith5051, Daar-al-Kutub-al-Ilmiyah, Beirut)

Excellence of Keeping One Fast
Syedna Sheikh Abdul Haq Narrator of Delhi narrates that the Holy Prophet said,
QUOTE :: Rajjab is one of the sacred months and its days are inscribed on the gate of sixth Heaven. If a person fasts for on day of this month and he keeps his fast clean though obedient devotion to Almighty Allah, the gate and the fasted day will seek repentance for that person in the court of Almighty Allah and will say, O Allah! Forgive him. If that person fails to make his fast complete through obedient devotion to Allah, the gate and the day will make no such plea for him to be forgiven. They will say that, your own Soul has betrayed you.
(Maa Thabata Bis-Sunnah, p342)

Last Words
Through the above narration, we learn that the purpose of fasting is not merely to stay hungry and thirsty, but it is vital to safeguard all limbs from sins. If despite fasting, sins are also committed then that is serious deprivation.
http://aulia-e-hind.com/Rajjab.htm