لَا إِلَٰهَ إِلَّا أَنْتَ سُبْحَانَكَ إِنِّي كُنْتُ مِنَ الظَّالِمِينَ
La ilaha illa anta subhanaka inni kuntu minaz-zalimin
除你外别无应受崇拜的。你是清净的。我确是不义者。
Recite during illness, hardship, or any difficulty
The Prophet (PBUH) said: 'The supplication of Dhun-Nun (Yunus) when he was in the belly of the whale - no Muslim ever calls upon Allah with it for anything but Allah responds to him.'