Sayyiduna Muhammad bin Jahsh (may Allah be pleased with him) said: One day we were sitting with the Prophet (peace and blessings be upon him) at the place of funeral prayers. He (peace and blessings be upon him) raised his head toward the sky, then placed his palm on his forehead and said: "Subhan Allah (Glory be to Allah)! What severity has Allah sent down from the heavens?" We fell silent and were frightened. The next morning I asked the Messenger of Allah (peace and blessings be upon him): O Messenger of Allah (peace and blessings be upon him)! What was the severity that was sent down? He (peace and blessings be upon him) said: "Concerning debt. By the One in Whose Hand is my soul! If a man were martyred in the path of Allah, then brought back to life, then martyred again, while he owed a debt, he would not enter Paradise until his debt was paid off on his behalf."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب البيوع / 10963