It was narrated that Sa’d ibn Abi Waqqaas (may Allaah be pleased with him) said: The Prophet (SallAllahu Alyhi wasallam) said: “The prayer of Dhu’l-Noon when he was in the belly of the fish: ‘Laa ilaaha illa Anta, subhaanaka inni kuntu min al-zaalimeen (There is no god but You, glory to You, verily I was one of the wrongdoers).’ A Muslim never calls upon his Lord with these words concerning any matter, but his prayer is answered.” (Narrated by al-Tirmidhi, 3505; classed as saheeh by al-Albaani in al-Silsilah al-Saheehah, 1644)