Ahmad ibn Abi al-Hawāree [may Allāh have mercy on him] said:
“I said to Sufyān ibn ‘Uyaynah [may Allāh have mercy on him]: ‘What is Zuhd in the worldly-life?’ He replied: ‘When you are thankful when favoured and patient when put to trial. This is Zuhd.’”
Siyar A’lām an-Nubalā’a, 8/468 | Al-Imām adh-Dhahabī [may Allāh have mercy on him]