On one particular occasion, someone wrote to Imaam Sufyaan, saying, 'Advise me, but be brief." Sufyaan wrote back the following reply:
" In the Name of Allah, The Most Beneficient the Most Merciful. May Allah protect both you and me from evil. My brother, know that the grief and worries of this world do not end and that its happiness is not lasting. So do not remiss (in your religious duties); otherwise, you will perish. And peace be upon you."
extracted from " The biography of Sufyaan Ath-Thauree"
compiled by Salaahud-Deen ibn Alee ibn 'Abdul-Maujood
darrussalam edition pg 170