"There is none worthy of worship except You. All purity belongs to You. Surely I am from among the wrongdoers."
"Laa ilaaha illaa anta subhaa naka innee kuntu mi nazzaa limeen."
1)It is mentioned in the Hadith that if any Muslim recites the above 40 times in the state of sickness,then if he recovers,all his sins are forgiven, but if he dies from it,he will be granted the reward of a Shaheed(martyr). (Haakim)
2)According to one Hadeeth, The Ismul-A'zam through which Duas are certainly granted and needs fulfilled is contained in the above duaa.