“A shia should be like this”

Once a man with his son came to Imam Ali (pbuh) as a guest… Imam Ali not only welcomed them warmly and settled them in a best place respectfully but he ordered to bring some foods for them as well… after dinner,the one who worked for Imam by the name of “ghanbar” brought a pitcher full of water and some towel for guests to wash their hands,but Imam took them to wash their hands himself, but the guest winced himself and didn’t let Imam to do that, but Imam said:(we are of the same kind, I want to be granted the divine reward by serving you, so why do you prohabit me from getting that reward?)but the guest didn’t accept it again when imam adjured him and asked him not to ban imam from serving him… so the guest accepted while he was very ashamed… when washing hands was done,Imam asked one of his sons named ”mohammad ebne hanafiye” to wash his son,s hands as well, and then Imam said:(if father of this son  weren’t here, I would like to wash his hands myself, but Allah likes the father to be respected more than the son when they are both present in the same place)… “ so shia should be like this”it has been quoted by Imam Hasan Askary(pbuh) when he told the story…