It is narrated from Hazrat Abu Huraira (may Allah be pleased with him) that the Holy Prophet (peace and blessings be upon him) said: When any one of you is in prayer, Satan comes to him and flatters him as a person flatters his animal. When he gains control over him, he binds his jaw or puts a bridle in his mouth. Hazrat Abu Huraira (may Allah be pleased with him) says: That is why you will see the first man swaying here and there and not remembering Allah, and you will see another man whose mouth is open and he is not remembering Allah.