Is it permissible to insert the Umrah ritual into the Hajj ritual after commencing Hajj?
Chapter on the Description of Hajj
Al-Mughni
Book of Hajj
Primary text
Inserting Umrah into Hajj after commencing Hajj is not permissible, and if performed, the Hajj is invalid, and the person does not become a Qarin (one performing Hajj and Umrah together). This opinion is held by Ali, Malik, Ishaq, Abu Thawr, and Ibn al-Mundhir. The evidence against it is the narration from al-Athram, on the authority of Abd al-Rahman ibn Nasr, whose father recounted accompanying Ali while Ali intended both Umrah and Hajj, and upon asking if he could join Ali's combined ritual after having already entered ihram for Hajj, Ali forbade it, stating it was only permissible if the initial ihram was for Umrah. Furthermore, inserting Umrah into Hajj does not yield a benefit beyond what the initial contract provided, thus it is invalid, similar to re-contracting for the same work.
Supporting text
Abu Hanifah holds that it is valid and the person becomes a Qarin, reasoning by analogy that since Hajj can be introduced into Umrah, Umrah can be introduced into Hajj, as both are acts of worship.