How can a indebted man who lost his business and whose salary is insufficient to pay his debt fulfill his obligation, and is he eligible for charity in accordance with the verse, "and for the emancipation of captives" (Al-Quran)?

He must strive to pay off his debt to its owner in installments, seek Allah's help, and economize his expenses. It is permissible for him to take from zakat (definition) to pay off his debt, based on Allah's saying regarding the recipients of zakat: "and for those in debt" (Al-Gharimin), and Al-Gharim (definition) is the debtor unable to pay. As for Allah's saying: "and for freeing captives" (Wa fi al-Riqab), it refers to freeing slaves and helping those who have contracted for their freedom.