The World Federation One Stop Fiqh

Ruling 969

If during obligatory prayers one intentionally recites one of the four surahs that contain an obligatory sajdah – as mentioned in Ruling 354 – it is obligatory that he performs sajdah after reciting the verse of sajdah. However, based on obligatory precaution, by performing the sajdah his prayer becomes invalid and it is obligatory that he performs the prayer again unless he performed the sajdah forgetfully. If he does not perform the sajdah, he can continue with the prayer but he will have committed a sin for not performing the sajdah.