Halakhah for Zevachim 38:12

And so [too,] that which they, may their memory be blessed, said (Zevachim 21b), [about] how much water needs to be in the basin - [that it is] no less than water that is fit for the [washing] of four people - as it is is stated, "And let Aharon and his sons wash their hands and their feet." And they were Aharon and Elazar and Itamar, and Pinchas was with them. And that all water is fit for sanctification - whether the water from a spring or the water of a pool (mikveh) - and they are disqualified by [passing the night]. And how is the commandment of the sanctification (Zevachim 19b) - that he places his right hand on his right foot and his left hand on his left foot and washes standing up and not sitting. As the sanctification of the hands and feet is included in the service, and all of the services of the Temple are [done while] standing up - as it is stated (Deuteronomy 18:5), "to stand and to serve." And all of this is for the loftiness of the [Temple]. And the rest of its details are elucidated in the second chapter of Zevachim.