It is narrated from Sayyiduna Uthman bin Abi al-As (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) used to say: "Allahumma inni a'udhu bika minal-faqri wa 'adhabil-qabri wa fitnatil-mahya wa fitnatil-mamat (O Allah, I seek refuge in You from poverty, the punishment of the grave, the trial of life and the trial of death)."
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 8356