"Knowing the cold and the warm"
The verse in the painting is a quotation from "A Gateless Barrier No. 23;Not Thinking About Good and Evil"
某甲雖在黄梅隨衆 實未省自己面目
今蒙指授入處 如人飲水冷暖自知
I have been practicing with everyone at Mount Huangbai, but I have not yet awakened to my true self. Now, having received the revelation,I understand it as clearly as a person who drinks water and knows whether it is cold or warm.
The characters written on the washbasin are taken from the Sutra of posthumous teachings.The central character "口" ("mouth") is shared with the surrounding characters and they are arranged to read "吾唯足知" ("I just know to be content.").