Aswad ibne-Asram Radiyallahu anhu narrates
That he requested:
O Rasulallah! (Sallallahu alaihi wasallam) Advise me.
He (Sallallahu alaihi wasallam) said:
Control your hands.
I said:
If my hands are not in my control,
then what else can be in my control?
Rasulullah Sallallahu alaihi wasallam said:
Control your tongue.
I said:
If my tongue is not in my control,
then what else can be in my control?
He (Sallallahu alaihi wasallam) then said:
Do not use your hands except for good works,
And do not say from your tongue except what is good.
{ Tabrani, Majma-uz-Zawaid }