Is offering a reward (ja'al) for services, such as returning lost property or defective work, permissible?

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The offering of a reward (ja'al) for returning lost animals (dallah), runaway slaves (abiq), and similar matters is permissible. This is the view of Abu Hanifa, Malik, and Al-Shafi'i, with no known dissent. The basis for this is the verse: {And for him who brings back the camel-load [of goods] is a reward, and I am its sponsor} (Quran 12:72). Evidence is also found in the tradition where the Companions accepted a flock of sheep as a reward for healing a chief by reading Al-Fatiha, which the Prophet, peace be upon him, permitted, stating, 'Take it, and give me a share from it.' This permissibility is necessitated by need, as the work involved might be inherently unknown, such as retrieving a lost item, where a fixed contract of lease (ijarah) is not suitable, and not everyone will volunteer the service.