Muharram is the month with which the Muslims begin their lunar Hijrah Calendar. It is one of the four sanctified months about which the Holy Quran says, "The number of the months according to Allah is twelve months (mentioned) in the Book of Allah on the day in which He created heavens and the earth. Among these (twelve months) there are four sanctified".
These four months, according to the authentic traditions are the months of Zulqadah, Zulhijjah, Muharram and Rajab. All the commentators of the Holy Quran are unanimous on this point, because the Holy Prophet in his sermon on the occasion of his last Hajj, has declared:
"One year consists of twelve months, of which four are sanctified months, three of them are in sequence; Zulqadah, Zulhijjah, Muharram, and the fourth is Rajab."
The specific mention of these four months does not mean that any other month has no sanctity, because the month of Ramadan is admittedly the most sanctified month in the year. But these four months were specifically termed as sanctified months for the simple reason that their sanctity was accepted even by the pagans of Makkah.
In fact, every month, out of the twelve, is originally equal to the other, and there is no inherent sanctity, which may be attributed to one of them in comparison to other months. When Allah Almighty chooses a particular time for His special blessings, then it acquires sanctity out of His grace.
Thus, the sanctity of these four months was recognized right from the days of Sayyidina Ibrahim. Since the Pagans of Makkah attributed themselves to Sayyidina Ibrahim they observed the sanctity of these four months and despite their frequent tribal battles, they held it unlawful to fight in these months.
In the Shariah of our Holy Prophet the sanctity of these months was upheld and the Holy Quran referred to them as the "sanctified months".