Only an Imam has the Authority to Wash the Body of an Imam for Burial

al-Husayn ibn Muhammad has narrated from Mu'alla ibn Muhammad from al-Hassan ibn Ali al-Washsha' from Ahmad ibn 'Umar al-Hallal or someone other than him who has said the following. "I said to al-Rida (a.s.), 'They argue with us that no one has the authority towash the body of an Imam for burial except." 

The narrator has said that the Imam (a.s.) then said, "How they would know who has washed him for burial? What did you say to them?" The narrator has said that I then said, May Allah take my soul in service for your cause, I told them that if my Imam would say that he has washed his body under the throne of the Lord he has told the truth.

If he would saay that he has washed it at the center of the earth he has told the truth." The Imam (a.s.) said, "It is not that way." I then asked him, "What then should I say to them (al-waqifiyya sect)?" The Imam (a.s.) said, "Tell them that I (al-Rida ) washed his body for burial." I then asked, "must I tell them that you have washed his body?" He said, "Yes, I have done so."

H 1001, Ch. 92, h 2

It is narrated from him from Mu'alla ibn Muhammad from Muhammad ibn Jumhur from Yunus from Talha who has said the following. "Once I said to al-Rida (a.s.), 'Is it true that only an Imam has the authority to wash the body of an Imam for burial?"

The Imam (a.s.) said, "Do you know who comes to wash his body for burial? One who is better than the one who is absence from his presence comes to wash. Those who came to Joseph in the well to help when his parents and family were absent from him."