The priest will then command that one bird be slaughtered into a clay vessel over fresh water.

and he is to slaughter one bird into a clay vessel over fresh water.

A clay vessel which the man with the discharge touches must be broken, and any wooden utensil must be rinsed in water.

Any clay vessel it is boiled in must be broken, and if it was boiled in a bronze vessel, then that vessel must be rubbed out and rinsed in water.

As for any clay vessel they fall into, everything in it will become unclean and you must break it.