The longest chapter which speaks of debt is Surah Bakarah (The Cow) which is the second chapter.

وَإِن كَانَ ذُو عُسْرَةٍ فَنَظِرَةٌ إِلَىٰ مَيْسَرَةٍ ۚ وَأَن تَصَدَّقُوا خَيْرٌ لَّكُمْ ۖ إِن كُنتُمْ تَعْلَمُونَ

Say: “If the debtor is in a difficulty, grant him time Till it is easy for him to repay. But if ye remit it by way of charity, that is best for you if ye only knew.” (2:280)

If the borrower cannot pay of debt within the deadline, then it is okay to extend the time for the borrower to pay off the debt.

وَاتَّقُوا يَوْمًا تُرْجَعُونَ فِيهِ إِلَى اللَّهِ ۖ ثُمَّ تُوَفَّىٰ كُلُّ نَفْسٍ مَّا كَسَبَتْ وَهُمْ لَا يُظْلَمُونَ

Say: “And fear the Day when ye shall be brought back to Allah. Then shall every soul be paid what it earned, and none shall be dealt with unjustly.” (2:281)

Every soul will be paid what it has earned in this world. Be scared of God the Almighty.

يَا أَيُّهَا الَّذِينَ آمَنُوا إِذَا تَدَايَنتُم بِدَيْنٍ إِلَىٰ أَجَلٍ مُّسَمًّى فَاكْتُبُوهُ ۚ وَلْيَكْتُب بَّيْنَكُمْ كَاتِبٌ بِالْعَدْلِ ۚ وَلَا يَأْبَ كَاتِبٌ أَن يَكْتُبَ كَمَا عَلَّمَهُ اللَّهُ ۚ فَلْيَكْتُبْ وَلْيُمْلِلِ الَّذِي عَلَيْهِ الْحَقُّ وَلْيَتَّقِ اللَّهَ رَبَّهُ وَلَا يَبْخَسْ مِنْهُ شَيْئًا ۚ فَإِن كَانَ الَّذِي عَلَيْهِ الْحَقُّ سَفِيهًا أَوْ ضَعِيفًا أَوْ لَا يَسْتَطِيعُ أَن يُمِلَّ هُوَ فَلْيُمْلِلْ وَلِيُّهُ بِالْعَدْلِ ۚ وَاسْتَشْهِدُوا شَهِيدَيْنِ مِن رِّجَالِكُمْ ۖ فَإِن لَّمْ يَكُونَا رَجُلَيْنِ فَرَجُلٌ وَامْرَأَتَانِ مِمَّن تَرْضَوْنَ مِنَ الشُّهَدَاءِ أَن تَضِلَّ إِحْدَاهُمَا فَتُذَكِّرَ إِحْدَاهُمَا الْأُخْرَىٰ ۚ وَلَا يَأْبَ الشُّهَدَاءُ إِذَا مَا دُعُوا ۚ وَلَا تَسْأَمُوا أَن تَكْتُبُوهُ صَغِيرًا أَوْ كَبِيرًا إِلَىٰ أَجَلِهِ ۚ ذَٰلِكُمْ أَقْسَطُ عِندَ اللَّهِ وَأَقْوَمُ لِلشَّهَادَةِ وَأَدْنَىٰ أَلَّا تَرْتَابُوا ۖ إِلَّا أَن تَكُونَ تِجَارَةً حَاضِرَةً تُدِيرُونَهَا بَيْنَكُمْ فَلَيْسَ عَلَيْكُمْ جُنَاحٌ أَلَّا تَكْتُبُوهَا ۗ وَأَشْهِدُوا إِذَا تَبَايَعْتُمْ ۚ وَلَا يُضَارَّ كَاتِبٌ وَلَا شَهِيدٌ ۚ وَإِن تَفْعَلُوا فَإِنَّهُ فُسُوقٌ بِكُمْ ۗ وَاتَّقُوا اللَّهَ ۖ وَيُعَلِّمُكُمُ اللَّهُ ۗ وَاللَّهُ بِكُلِّ شَيْءٍ عَلِيمٌ

Say: “O ye who believe! When ye deal with each other, in transactions involving future obligations in a fixed period of time, reduce them to writing Let a scribe write down faithfully as between the parties: let not the scribe refuse to write: as Allah Has taught him, so let him write. Let him who incurs the liability dictate, but let him fear His Lord Allah, and not diminish aught of what he owes. If they party liable is mentally deficient, or weak, or unable Himself to dictate, Let his guardian dictate faithfully, and get two witnesses, out of your own men, and if there are not two men, then a man and two women, such as ye choose, for witnesses, so that if one of them errs, the other can remind her. The witnesses should not refuse when they are called on (For evidence). Disdain not to reduce to writing (your contract) for a future period, whether it be small or big: it is juster in the sight of Allah, More suitable as evidence, and more convenient to prevent doubts among yourselves but if it be a transaction which ye carry out on the spot among yourselves, there is no blame on you if ye reduce it not to writing. But take witness whenever ye make a commercial contract; and let neither scribe nor witness suffer harm. If ye do (such harm), it would be wickedness in you. So fear Allah. For it is Good that teaches you. And Allah is well acquainted with all things. If ye are on a journey, and cannot find a scribe, a pledge with possession (may serve the purpose). And if one of you deposits a thing on trust with another, let the trustee (faithfully) discharge his trust, and let him Fear his Lord conceal not evidence; for whoever conceals it, - his heart is tainted with sin. And Allah knoweth all that ye do.” (2:282)

This is the longest verse in Holy Quran which makes it quite significant.

  1. Write down and record the transactions
  2. The person borrowing the money must write the transaction
  3. Should the person not able to write then a guardian can write it
  4. Get two men as witnesses, if there are not two men then one man and one woman
  5. The witness must not refuse when called on for evidence
  6. If a transaction is carried on the spot then it is fine if there is no writing
  7. Always have witnesses whenever there is a business contract, no scribe or witness must suffer harm

First priority is given to the lender if the borrower has died or passed away. Pay the debt off equal to what was borrowed. When the borrower passes away or dies, all the debt he or she owns must be paid off from the previous wealth before given to the beneficiaries.

۞ وَإِن كُنتُمْ عَلَىٰ سَفَرٍ وَلَمْ تَجِدُوا كَاتِبًا فَرِهَانٌ مَّقْبُوضَةٌ ۖ فَإِنْ أَمِنَ بَعْضُكُم بَعْضًا فَلْيُؤَدِّ الَّذِي اؤْتُمِنَ أَمَانَتَهُ وَلْيَتَّقِ اللَّهَ رَبَّهُ ۗ وَلَا تَكْتُمُوا الشَّهَادَةَ ۚ وَمَن يَكْتُمْهَا فَإِنَّهُ آثِمٌ قَلْبُهُ ۗ وَاللَّهُ بِمَا تَعْمَلُونَ عَلِيمٌ

Say: “If ye are on a journey, and cannot find a scribe, a pledge with possession (may serve the purpose). And if one of you deposits a thing on trust with another, Let the trustee (Faithfully) discharge His trust, and let him fear his Lord. Conceal not evidence; for whoever conceals it,- His heart is tainted with sin. And Allah Knoweth all that ye do.” (2:283)

۞ وَلَكُمْ نِصْفُ مَا تَرَكَ أَزْوَاجُكُمْ إِن لَّمْ يَكُن لَّهُنَّ وَلَدٌ ۚ فَإِن كَانَ لَهُنَّ وَلَدٌ فَلَكُمُ الرُّبُعُ مِمَّا تَرَكْنَ ۚ مِن بَعْدِ وَصِيَّةٍ يُوصِينَ بِهَا أَوْ دَيْنٍ ۚ وَلَهُنَّ الرُّبُعُ مِمَّا تَرَكْتُمْ إِن لَّمْ يَكُن لَّكُمْ وَلَدٌ ۚ فَإِن كَانَ لَكُمْ وَلَدٌ فَلَهُنَّ الثُّمُنُ مِمَّا تَرَكْتُم ۚ مِّن بَعْدِ وَصِيَّةٍ تُوصُونَ بِهَا أَوْ دَيْنٍ ۗ وَإِن كَانَ رَجُلٌ يُورَثُ كَلَالَةً أَوِ امْرَأَةٌ وَلَهُ أَخٌ أَوْ أُخْتٌ فَلِكُلِّ وَاحِدٍ مِّنْهُمَا السُّدُسُ ۚ فَإِن كَانُوا أَكْثَرَ مِن ذَٰلِكَ فَهُمْ شُرَكَاءُ فِي الثُّلُثِ ۚ مِن بَعْدِ وَصِيَّةٍ يُوصَىٰ بِهَا أَوْ دَيْنٍ غَيْرَ مُضَارٍّ ۚ وَصِيَّةً مِّنَ اللَّهِ ۗ وَاللَّهُ عَلِيمٌ حَلِيمٌ

Say: “In what your wives leave, your share is a half, if they leave no child; but if they leave a child, ye get a fourth; after payment of legacies and debts. In what ye leave, their share is a fourth, if ye leave no child; but if ye leave a child, they get an eighth; after payment of legacies and debts. If the man or woman whose inheritance is in question, has left neither ascendants nor descendants, but has left a brother or a sister, each one of the two gets a sixth; but if more than two, they share in a third; after payment of legacies and debts; so that no loss is caused (to any one). Thus is it ordained by Allah. and Allah is All-knowing, Most Forbearing.” (4:12)