Those who hold that this is not a condition argue that Hajj includes obligatory acts whose omission is compensated for by a sacrifice, but which are not conditions for its validity. If a pilgrim omits them, deliberately or inadvertently, he compensates for them with a sacrifice, unlike prayer.

As for prayer, are there obligatory acts whose omission does not invalidate it under any circumstances, or are there not? Or does their omission leave it valid only when they are forgotten? This is a well-known matter of disagreement. Abū Hanīfa considers certain acts obligatory in prayer without their omission invalidating it under any circumstances, such as reciting al-Fātiha and remaining still in the prayer postures. Ahmad takes a similar position according to one of the two views in his school: he considers congregational prayer obligatory but does not make it a condition for the prayer’s validity. According to the well-known view reported from Ahmad, some obligatory acts in prayer, if omitted inadvertently, are compensated for by the two prostrations for forgetfulness, while others require no compensation, such as keeping free of impurities, according to the well-known view reported from him. Likewise, Mālik considers keeping free of impurities and similar matters obligatory in prayer, yet holds that someone who omits them must repeat the prayer within its prescribed time, but not after that time has passed. These positions are well known in their respective schools.

As for the “second question”: if a woman menstruates and becomes pure before the Day of Sacrifice, she is excused from the arrival circumambulation and performs the circumambulation of ifādah on the Day of Sacrifice or afterward, while she is pure. Likewise, if she performs the circumambulation of ifādah while pure, then menstruates and does not become pure before departing, she is excused from the farewell circumambulation. This accords with the Sunnah of the Messenger of Allah (peace and blessings be upon him), who granted this concession to a woman who performed circumambulation while pure and then menstruated, excusing her from the farewell circumambulation:

“His wife Safiyya, the Mother of the Believers, began menstruating on the Day of Sacrifice. He asked, ‘Will she hold us back?’ They replied, ‘She