It is narrated from Sayyiduna Muhammad bin Abdullah bin Jahsh (may Allah be pleased with him) that the Prophet (peace and blessings be upon him) said: "Jibril (peace be upon him) said to me: 'If a servant is killed in the path of Allah while he has a debt upon him, he will not enter Paradise until his debt is paid off on his behalf.'"
Hadith Referenceالمعجم الكبير للطبراني / باب الميم / 16608