لَا إِلَٰهَ إِلَّا أَنْتَ سُبْحَانَكَ إِنِّي كُنْتُ مِنَ الظَّالِمِينَ
La ilaha illa anta subhanaka inni kuntu minaz-zalimin
Hakuna mungu isipokuwa Wewe. Utukufu ni Wako. Hakika mimi nilikuwa miongoni mwa madhalimu.
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.'