It is narrated from Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) and Sayyidah Aisha (may Allah be pleased with her) that when the Prophet (peace and blessings be upon him) was afflicted with the illness of his passing, he would repeatedly cover his blessed face with a sheet, and when he felt discomfort, we would remove the sheet from his face. The Prophet (peace and blessings be upon him) was saying, "May Allah's curse be upon the Jews and Christians; they made the graves of their prophets places of prostration." Sayyidah Aisha (may Allah be pleased with her) says that in fact, the Prophet (peace and blessings be upon him) was warning people against their action so that they would not fall into it.