It is reported that ʿAbd Al-ʿAzīz b. Abī Rawwād – Allāh have mercy on him – said to a man:

Whoever does not take exhortation [and is not effected] by three things, will not be exhorted by anything: Islām, the Qurān and old age (graying).

Ibn Abī Al-Dunyā, Al-ʿUmr Wa Al-Shayb #40