Shaddad and as-Sunabihi (Radiyallahu `anhuma) narrated that, Allah’s Messenger (Sallallaahu `alayhi wa sallam) said,

“Allah who is Great and Glorious says, ‘When I afflict a servant of Mine who is a believer and he praises Me, for the affliction I have brought upon him; he will rise from that couch of his as sinless as he was the day his mother gave birth to him.’

The Rabb, Who is Blessed and Exalted, will say, ‘I fettered and afflicted My servant, so record for him what you were recording for him when he was well.“

(Tirmidhi 1579 and Ahmad)