Pinchas was sitting shiva. Shmuel made a shiva call and noticed Pinchas' nails were really long and asked him why he didn't cut his nails since the halacha is like Rabi Yosi that nail cutting is permissible on Chol HaMoed and aveilus. Pinchas said, "If you'd be sitting shiva, would you be so callous?!" Shmuel's relative died because of Pinchas' comment. When Pinchas made a shiva call, Shmuel threw his nails at Pinchas in anger and said, "What, you don't hold of 'there is a covenant for the lips'?!"