and through it they altered the appointed times of the pilgrimage and the sacred months, so that they would perform the pilgrimage sometimes in Muharram and sometimes in Safar, until it eventually returned to Dhū al-Hijjah. This continued until Allah sent the one who restored the religion of Abraham. When he, may Allah bless him and grant him peace, performed his Farewell Pilgrimage, time had come full circle, and his pilgrimage fell in Dhū al-Hijjah. In his famous sermon, recorded in the two Sahīh collections and elsewhere, he said:

“Time has come full circle, returning to its state on the day Allah created the heavens and the earth. The year consists of twelve months, four of which are sacred: three consecutive months—Dhū al-Qa‘dah, Dhū al-Hijjah, and Muharram—and Rajab of Mudar, which falls between Jumādā and Sha‘bān.”

Before that, the pilgrimage had not fallen in Dhū al-Hijjah; even Abū Bakr’s pilgrimage in the year nine took place in Dhū al-Qa‘dah. This was one of the reasons why the Prophet, may Allah bless him and grant him peace, delayed performing the pilgrimage.

Allah Most High revealed:

“Indeed, the number of months with Allah is twelve months, in the decree of Allah from the day He created the heavens and the earth; of these, four are sacred. That is the upright religion.”

Allah thus declared that this is the upright religion, making clear that alternatives involving intercalation and other customary practices of nations are not upright, because of the deviation and disorder they entail. The day and the week are analogous to the month and the year. The day is a natural unit, extending from the rising of