This is fairly common practice in places where it's minus 10c outside and you have to get your wife (or more likely your slave) to go to the well, get the water, carry the water, heat the water, and carry the water to you.

"Every morning a woman comes and brings a tub of water and places it before her master. He proceeds to wash his face and hands in this and then his hair, combing it out over the tub. Then he blows his nose and spits into the tub, and leaving no dirt behind, conveys it all into this water. When he has finished, the girl carries the tub to the man next to him, who does the same. And so she continues carrying the tub from one to another, until each of those in the house has blown his nose and spit into the tub, and has washed his face and hair."

That's fucking nasty. Imagine being the twentieth dude who has to see 19 other dudes' nasty loogie and snot floating in some filthy tub and then washing your face and hands from the same tub because he didn't say they had two tubs, one for the hands/face and one for the loogie/snot. It really comes off as him insulting them for not knowing how to wash themselves properly.