521. The Mufradah Umrah falls into two categories: obligatory, and mostahab. The obligatory one is of two classifications: fundamental obligation, and secondary obligation.
522. The fundamental obligation of the Mufradah Umrah: is to be preformed [at least] once, along with the particular criteria of the Hajj, as specified by the Shar. The obligation of the [Mufradah] Umrah upon the people of Makkah, or those to whom the ruling of people of Makkah apply, is not conditional upon their ability to perform the Hajj as well, for they may be mostatee able to perform the Umrah but not the Hajj, or the Hajj but not the Umrah, since the Hajj and the Mufradah Umrah are two different rites, independent of one other.
523. One who is remote from Makkah is not obliged to perform the Mufradah Umrah, but he is obliged to perform the Tamattu Umrah and the Tamattu Hajj. However, if he was able to perform the [Mufradah] Umrah but not the Hajj, then it is obligatory for him to perform the Mufradah Umrah, as a precaution. If he failed to perform it [The Mufradah Umrah] and died, as a precaution it should be perform as qadha' by proxy.
524. The agent who himself is not mostatee' to perform the Hajj, after finishing his proxy Hajj job, as an obligatory precaution should perform the Mufradah Umrah for himself, if he became mostatee' only to do the Umrah.
525. The secondary obligation of the Mufradah Umrah arises through nadhr [vow], promise, oath, hire, as a condition of a contract, or through corruption of the Hajj, or through missing the Hajj, where, in the latter case, he would only be released from the ihraam [of the Hajj] by [performing] the Mufradah Umrah.
526. The Mufradah Umrah is obligatory for one who wishes to enter the holy city of Makkah, since it is not permitted for one who wishes to enter Makkah to cross any of the miqaat's except by declaring and assuming ihraam.
[37] As for the individual who wish to enter the Haram but not the holy city of Makkah, the likelihood is that he is not obliged to the Mufradah Umrah [i.e. he is not obliged to assume ihraam].
527. Apart from the obligatory grounds, it is mostahab desirable to perform the Mufradah Umrah once a month, and its desirability is emphasised during the month of Rajab.
528. If one performs two consecutive [Mufradah] Umrah either in person or by proxy the reward is greater if there is a time gap of ten days, than if there were less. In any case, the reward for them is great. If [one was performing] the two Umrah's for two different persons, then the issue of time gap [between the two Umrah's] would not be applicable.
Notes:
[37] and he can only be released from the state of ihraam by performing the Umrah.