THE CORRECT PROSTRATION (SAJDAH) IN THE PRAYER

[Rajaee]

As one of the elementary acts of the prayer, "sajdah" has to be performed in this way:

In every rakʿah of the obligatory and recommended prayers, one must perform two sajdahs after rukūʿ. A sajdah is performed when one places his forehead on the ground in a particular manner with the intention of humility [before Allah]. While performing a sajdah in prayers, it is obligatory that the palms of both hands, both knees, and both big toes be placed on the ground. Based on obligatory precaution, [for the purposes of sajdah] the ‘forehead’ refers to its middle area, i.e. the rectangular area when two imaginary lines are drawn between the place where the eyebrows begin in the middle of the forehead up to the point where the hair grows.

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Two sajdahs together comprise one rukn, and if someone does not perform both of them in obligatory prayers in one rakʿah – even if this is due to forgetfulness or not knowing the ruling – his prayer is invalid. The same applies, based on obligatory precaution, if one adds two sajdahs in one rakʿah forgetfully or due to inculpable ignorance (al‑jahl al‑quṣūrī). (Inculpable ignorance is when someone has a valid excuse for not knowing.)