Haya (hiring) ya ƙunshi amfani da fa'idar abin da aka yi haya. Dangane da ma'aikaci, haya tana nufin amfani da ƙwazonsa. Wajibi ne a cikin hayar ma'aikaci a bayyana aikin, lokacin aikin, albashin da ƙwazon. Dole ne a bayyana aikin don kada ya zama ba a sani ba, domin hayar da ta dogara da aikin da ba a sani ba ba ta inganta ba (Fasid). Haka kuma wajibi ne a bayyana lokacin aikin, kamar kullum, ko kowane wata, ko kowace shekara. Hakanan wajibi ne a bayyana albashin ma'aikaci. Ibn Mas'ud ya ce: Annabi ﷺ ya ce: "Idan ɗayanku ya ɗauki ma'aikaci, to ya zama wajibi ya sanar da shi albashinsa." Haka kuma wajibi ne a bayyana ƙwazon da ma'aikacin zai yi. Saboda haka, ba a halatta a nemi ma'aikaci aikin da ya wuce ƙarfinsa ba. Allah (SWT) ya ce:

Hiring involves utilising the benefit of the hired thing. With regard to the worker, hiring is utilising his effort. It is necessary in hiring a worker, to define the work, the period of work, the wage and the effort. The work has to be defined so as not to become unknown, because hiring based on unknown work is invalid (Fasid). It is also necessary to define the period of work, such as daily, monthly or yearly. Similarly, the wage of the worker has to be defined. Ibn Mas’oud said: The Prophet (pbuh) (pbuh) said: “If any one of you employed a worker then He has to inform Him of his wage.” It is also necessary to define the effort that the worker has to expend. Accordingly it is not allowed to demand of the worker work that is beyond his capacity. Allah (swt) said:

"Allah does not burden a soul beyond its capacity." [Al-Baqarah: 286] The Prophet ﷺ said: "If I command you to do something, do of it as much as you are able," as narrated by Bukhari and Muslim from Abu Hurairah. The worker should not be asked to undertake effort except that which is within his ordinary capacity. Since a precise scale cannot measure effort, defining the number of working hours each day is the best possible measure. In addition, the type of work has to be defined as well, such as digging hard or soft soil, forging metal, or cutting stones. This also determines the amount of effort. The work is thus defined by stating its type, duration, wage and the effort spent in it. When the Shar'a permitted employing a worker, it laid out provision for defining his work in terms of its type, duration, wage and effort. The wage received by the worker, in return for his execution of the work, is the property he has earned as a result of the effort he spent.

“Allah burdens not a person beyond his scope.” [Al-Baqarah: 286] The Prophet (pbuh) (pbuh) said: “If I commanded you of something, do of it as much as you can”, as narrated by Bukhari and Muslim from Abu Hurairah. The worker should not be asked to undertake effort except that which is within his ordinary capacity. As a real scale cannot measure effort, defining the number of working hours every day is the best possible measure. In addition the type of work has to be defined as well, such as digging hard or soft soil, forging a metal or cutting stones. This also determines the amount of effort. The work would have thus been defined by stating its type, duration, wage and the effort spent in it.When Shar’a allowed employing a worker, it laid out provision for defining his work in terms of the type, duration, wage and effort. The wage received by the worker, in return for his execution of the work, is the property He accrued as a result of the effort He spent.