Reference: Siyar A’laam an-Nubalaa – Volume 12, Page 492
[In preparation for their burial], al-Muzanee would wash the dead as an act of worship, and he would say:
I endured [the experience of] washing [the bodies of] the dead – [intending by doing so] to soften my heart, until it softened.
And he was the one who washed [the body of al-Imaam] ash-Shaafi’ee rahima-hullaah.