Muhammad ibn Ahmad ibn Dawud, from his father, who said: Muhammad ibn Abdullah al-Himyari narrated to us, saying: I (al-Himyari) wrote to the Jurist (peace be upon him), asking him about a man who visits the graves of the Imams, peace be upon them; ‘Is it permissible for him to prostrate upon the grave or not? And is it permissible for someone who prays near their graves to stand behind the grave and make the grave his Qiblah? And to stand by its head or feet? And is it permissible to stand in front of the grave and pray with the grave behind him, or not? So He (the Jurist عليه السلام), peace be upon him, replied and I read the tawqi’ (written response), and from it I (al-Himyari) copied; "As for prostration on the grave, it is not permissible in an obligatory or supererogatory prayer, nor during a visitation. Rather, he should place his right cheek on the grave (of Imam عليه السلام). As for prayer, it should be behind the grave, making it (the grave of Imam عليه السلام) as his Imam (leader of prayer), and it is not permissible to pray in front of it, because the Imam (of prayer) is not preceded. He may pray to its right or left."