They differed regarding the prostration of forgetfulness, whether it is obligatory or a sunnah. Some say that it is a sunnah, and some say that it is obligatory, but it is not a condition for the validity of the prayer. Malik distinguished between the prostration of forgetfulness in actions, and the prostration of forgetfulness in words, and between addition and subtraction, so he said the prostration of forgetfulness, which Incomplete actions are obligatory, and according to him, they are among the conditions of prayer.