The Waajib is divided or categorised in accordance to different considerations. As such, there is a division in respect to its performance (Adaa’), another in respect to its evaluation (Taqdeer), a third in respect to its designation and a fourth in respect to the one who has been charged with it (Mukallaf).

Waajib Mutlaq and Waajib Muqayyad (The unrestricted obligation and the restricted obligation):

1 – Al-Waajib Al-Mutlaq (unrestricted obligation):

This is what the Shaari’ (Legislator) has requested to be done without restricting it to a specific time and an example of this type is the Qadaa’ of Ramadhaan for the one who did not fast due to a Shar’iy ‘Udhr (excuse/reason) like sickness or travelling. That is because he can make Qadaa’ for it when he wishes without it being restricted to a specified year. This is the opinion of some of the Fuqahaa’ in this issue including the Hanafiyah. Others however have stipulated that it is a condition for the person to make up (Qadaa’) for what he missed before the coming of the Ramadhaan that follows the Ramadhaan in which he didn’t fast, if the Mukallaf is capable of doing that (i.e. within a year).

Other examples include the Kaffaaraat (expiations) and unrestricted vows (Nudhoor). So whoever breaks one’s oath or vow, without being restricted to a specific time, can undertake the required expiation (Kaffaarah) directly after his breaking and undertake his vow immediately if he wishes to or he can delay it until a time of his choosing.

2 – Al-Waajib Al-Muqayyad (restricted obligation):

This is what the Shaari’ has requested to be undertaken and specified a specific and defined time for its performance or undertaking. Examples of this include the five obligatory prayers and the fasting of Ramadhaan because it is not permitted to undertake them before their set and specified time and the Mukallaf is sinful if he delays the action from its time without a legitimate legal excuse.

The Waajib Al-Muqayyad is divided into two categories: Waajib Muwassa’ and Waajib Mudayyaq.

A – Al-Waajib Al-Muwassa’: That which the time specified for its performance provides some time, room or expansiveness for it and other actions of its type to be performed. That is like the Zhohr prayer for example.

B – Al-Waajib Al-Mudayyaq (narrow): That which its specified time for its performance does not provide room for others of its type (to be performed) and this is like the fasting of Ramadhaan. That is because its time does not provide room except for the fulfilment of the obligatory fasting within it.