Is a guarantee valid if it is conditioned on an event other than the arrival of the guaranteed person, such as saying, 'If you bring him at such a time, otherwise I guarantee your money owed by so-and-so,' or 'When Zayd arrives, I guarantee so-and-so,' or 'When the Hajj pilgrim arrives, I guarantee so-and-so,' or 'I guarantee so-and-so for a month'?
Chapter on Guarantee (Daman)
Al-Mughni
Book of Assignment (Transfer of Debt)
Primary text
The guarantee is invalid according to the Qadi, which is the view of Al-Shafi'i and Muhammad ibn al-Hasan. This is because suspending the guarantee upon a hazard, such as the coming of rain or the blowing of the wind, is impermissible. Furthermore, establishing a right for a specific person cannot be suspended by a condition or limited by a time frame, similar to a gift (Hiba).
Supporting text
Al-Sharif Abu Ja'far and Abu al-Khattab hold that the guarantee is valid. This is the position of Abu Hanifa and Abu Yusuf, based on the reasoning that the guarantor associated the liability with a cause of existence, which necessitates validity, like guaranteeing against eviction (Darak).