The month of Muharram is the first month of
the Arabic year, and it is one of the four
sacred months of Allaah. Allaah says
(interpretation of the meaning):
“Verily, the number of months with Allaah is
twelve months (in a year), so was it ordained
by Allaah on the Day when He created the
heavens and the earth; of them four are
Sacred (i.e. the 1st, the 7th, the 11th and
the 12th months of the Islamic calendar).
That is the right religion, so wrong not
yourselves therein”
[al-Tawbah 9:36]
al-Bukhaari (3167) and Muslim (1679)
narrated from Abu Bakrah (may Allaah be
pleased with him) that the Prophet (peace
and blessings of Allaah be upon him) said:
“The division of time has turned to its
original form which was current the day
Allaah created the heavens and earth. The
year consists of twelve months of which four
are sacred: three consecutive months, Dhu’l-
Qa’dah, Dhu’l-Hijjah and Muharram, and
Rajab of Mudar which comes between
Jumada and Sha’baan.”
It was proven from the Prophet (peace and
blessings of Allaah be upon him) that the
best fasting after Ramadaan is fasting in the
month of Muharram. It was narrated that
Abu Hurayrah (may Allaah be pleased with
him) said: The Messenger of Allaah (peace
and blessings of Allaah be upon him) said:
“The best fasting after Ramadaan is the
month of Allaah Muharram, and the best
prayer after the obligatory prayer is prayer
at night.” Narrated by Muslim, 1163.
With regard to the phrase “the month of
Allaah”, mentioning the month in
conjunction with Allaah is a sign of its great
status. Al-Qaari said: it seems that what is
meant is all of the month of Muharram.
But it was proven that the Prophet (peace
and blessings of Allaah be upon him) did not
fast any month in full apart from Ramadaan,
so this hadeeth is to be understood as
meaning that it is it is encouraged to fast a
lot in the month of Muharram, not to fast the
whole month.
And Allaah knows best.

Jazakumullahu khair. May Allah make it easy for us.

Aameen. buh pls av got a question..if muharram is d next best time to fast after rammadan, then what happens to or what category is the sitta shawwal