Hawzah News Agency – Imam Ali (AS), in his will to his son Imam Hasan (AS) said,

أحيِ قَلبَكَ بالمَوعِظَةِ، وأمِتْهُ بالزَّهادَةِ .

'Revive your heart with exhortations, and kill it will asceticism.'

Source: Nahj al-Balagha, Letter 31