Sayyiduna Abu Hurairah (may Allah be pleased with him) narrated that the Messenger of Allah (peace and blessings be upon him) said: When the call to prayer (adhan) is given, Satan flees while passing wind so that he does not hear the adhan. When the adhan is finished, he returns. Then when the iqamah is pronounced, he flees again. But as soon as the iqamah is finished, he comes back and puts various doubts into the heart of the worshipper and says, "Remember such and such thing." In this way, he reminds him of things which he did not have in his mind before, so much so that the worshipper does not remember how many rak‘ahs he has prayed. Therefore, if anyone does not remember whether he has prayed three or four rak‘ahs, he should perform two prostrations of forgetfulness while sitting.