Wajibs of prayer
What is the decree about wajib in prayer?
There are some wajibs of prayer just like its fards. When those wajibs are fulfilled, the incomplete parts of the prayer are regarded to have been completed.
If one or more wajibs are abandoned by mistake, the prayer is valid but its reward decreases. Sajdah as-sahw is performed at the end of the prayer in order to complete the deficiency. Thus, the prayer is completed and the reward does not decrease. If wajibs are abandoned deliberately, that prayer needs to be performed again; sajdah as-sahw is not enough to complete that prayer.
Primary wajibs of prayer are as follows:
1 - To read the chapter of al-Fatiha in prayers. It is fard to read the chapter of al-Fatiha according to the other three madhhabs.
2 - To utter the opening takbir fully by saying Allahu Akbar, not by saying Allah only.
3 - To read a short additional chapter, three short verses or one long verse after the chapter of al-Fatiha. An additional chapter or verses are read in the first two rak'ahs of fard prayers.
In supererogatory prayers, an additional chapter or verses are read after the chapter of al-Fatiha in all rak'ahs.
It is sunnah to read an additional chapter or verses in the other madhhabs.
4 - To read the chapter of al-Fatiha before an additional chapter or verses.
5 - Not to perform a rukn more than its legitimate amount; for instance, not to perform 3 sajdahs instead of 2 sajdahs. If something like that is done, a wajib is regarded to have been abandoned.
6 - To put the nose on the ground/floor along with the forehead in sajdah.
7 - To perform the first sitting in three or four-rak'ah prayers after the second rak'ah.
8 - To stand up for the third rak'ah in three or four rak'ah prayers, witr prayers and the sunnah of the noon prayer as soon as reading at-Tahiyyat without losing any time.
If a person does not stand up after at-Tahiyyat and reads salawat and other duas, a wajib is regarded to have been abandoned; so, sajdah as-sahw becomes necessary.
9 - To read at-Tahiyyat in the first and second sittings of prayers.
10 - To perform each wajib in its proper place; not to abandon or delay them. Not to delay the fards. For instance, to bow down without losing any time after finishing qira'ah.
Sajdah as-sahw becomes necessary if a fard is delayed and if a wajib is abandoned and delayed. If a fard is abandoned, the prayer is invalidated.
11 - It is wajib for a person who performs the noon and afternoon prayers alone to read silently (in a way that he will hear it only himself). It is necessary to read like that in the supererogatory prayers that are performed during the day. It is permissible to read silently or aloud in the morning, evening and night prayers.
12 - In the prayers that are performed in congregation, it is wajib for the imam to read aloud in all rak'ahs of the morning, eid, Friday, tarawih and witr prayers, to read silently in all rak'ahs of the noon and afternoon prayers, in the third rak'ah of the evening prayer and the third and four rak'ahs of the night prayer. He needs to read aloud in the first two rak'ahs of the evening and night prayers.
13 - To read the qunut supplications and to utter the qunut takbir in the witr prayer.