What to do with a Heedless Heart – Shaykh al-Uthaymeen (rahimahullah)
Shaykh al-Uthaymeen (rahimahullah):
Whenever (you find) your heart heedless, and you are preoccupied with the worldly life, then go to the graves and contemplate about those people (in the graves), yesterday they were upon the earth, just as you are now.
Sharh Riyadh as-Saaliheen v.3 pg.473