Quote from : From MTV to Mecca: How Islam Inspired My Life Book

A sick person is Allah’s guest for as long as he is ill. Every day he is sick, God gives him countless rewards, as long as he says ‘ al hamdulillah’, praise be to God, and does not fight it and complain. When God returns to him his health, he expiates his sins and gives him the status of the newly-born (completely pure and free of any sin). Illness is a mercy and a blessing.