The Messenger of Allah used to say these words in his supplication: "Allahumma inni a'udhu bika min ghalabatid-dain, wa ghalabatil-'aduwwi, wa shamatatil-a'da'. (O Allah, I seek refuge with You from being overwhelmed with debt, from being overpowered by the enemy and from the enemy rejoicing over my misfortunes.)'"
Sunan an-Nasa'i Book 50, Hadith 48