What are the sacred months?

Their number and description come in a single verse:

“Indeed, the number of months with Allah is twelve lunar months in the register of Allah from the day He created the heavens and the earth; of these, four are sacred. That is the correct religion i.e., way, so do not wrong yourselves during them. And fight against the disbelievers collectively as they fight against you collectively. And know that Allah is with the righteous who fear Him.” (Qur’an 9:36)

They are Dhū al-Qa‘da, Dhū al-Hijja and Muharram — three consecutive — and Rajab, which stands alone among them.

What follows from their sanctity?

• Sin in them is graver. The verse forbids wronging yourself in them specifically, not because wrongdoing is permitted outside them, but because in them it is heavier.
• Redoubled attention to good works.
• Fighting in them was forbidden in the original legislation, and scholars have discussed its ruling today.

What does not follow:

• There is no prescribed prayer, no prescribed remembrance and no celebration for them.
• What circulates about singling Rajab out with a prayer, an ‘Umra or a particular night has no basis, and is treated in a separate question.

What is established in them:

• Fasting ‘Āshūrā’ in Muharram, among the best fasts after Ramadan.
• The day of ‘Arafa in Dhū al-Hijja, for those not on Hajj.
• The first ten days of Dhū al-Hijja, among the greatest days of the year for deeds.

The practical benefit is that the honouring of a time in the law is known by text rather than by preference: where an act is reported, it is done; where none is, the month is honoured by leaving sin in it and striving in what is already prescribed, not by inventing a rite for it.