Al-Baqarah - 2:282

يَا أَيُّهَا الَّذِينَ آمَنُواْ إِذَا تَدَايَنتُم بِدَيْنٍ إِلَى أَجَلٍ مُّسَمًّى فَاكْتُبُوهُ وَلْيَكْتُب بَّيْنَكُمْ كَاتِبٌ بِالْعَدْلِ وَلاَ يَأْبَ كَاتِبٌ أَنْ يَكْتُبَ كَمَا عَلَّمَهُ اللّهُ فَلْيَكْتُبْ وَلْيُمْلِلِ الَّذِي عَلَيْهِ الْحَقُّ وَلْيَتَّقِ اللّهَ رَبَّهُ وَلاَ يَبْخَسْ مِنْهُ شَيْئًا فَإن كَانَ الَّذِي عَلَيْهِ الْحَقُّ سَفِيهًا أَوْ ضَعِيفًا أَوْ لاَ يَسْتَطِيعُ أَن يُمِلَّ هُوَ فَلْيُمْلِلْ وَلِيُّهُ بِالْعَدْلِ وَاسْتَشْهِدُواْ شَهِيدَيْنِ من رِّجَالِكُمْ فَإِن لَّمْ يَكُونَا رَجُلَيْنِ فَرَجُلٌ وَامْرَأَتَانِ مِمَّن تَرْضَوْنَ مِنَ الشُّهَدَاء أَن تَضِلَّ إْحْدَاهُمَا فَتُذَكِّرَ إِحْدَاهُمَا الأُخْرَى وَلاَ يَأْبَ الشُّهَدَاء إِذَا مَا دُعُواْ وَلاَ تَسْأَمُوْاْ أَن تَكْتُبُوْهُ صَغِيرًا أَو كَبِيرًا إِلَى أَجَلِهِ ذَلِكُمْ أَقْسَطُ عِندَ اللّهِ وَأَقْومُ لِلشَّهَادَةِ وَأَدْنَى أَلاَّ تَرْتَابُواْ إِلاَّ أَن تَكُونَ تِجَارَةً حَاضِرَةً تُدِيرُونَهَا بَيْنَكُمْ فَلَيْسَ عَلَيْكُمْ جُنَاحٌ أَلاَّ تَكْتُبُوهَا وَأَشْهِدُوْاْ إِذَا تَبَايَعْتُمْ وَلاَ يُضَآرَّ كَاتِبٌ وَلاَ شَهِيدٌ وَإِن تَفْعَلُواْ فَإِنَّهُ فُسُوقٌ بِكُمْ وَاتَّقُواْ اللّهَ وَيُعَلِّمُكُمُ اللّهُ وَاللّهُ بِكُلِّ شَيْءٍ عَلِيمٌ
[2:282]
O you who believe! when you deal with each other in contracting a debt for a fixed time, then write it down; and let a scribe write it down between you with fairness; and the scribe should not refuse to write as Allah has taught him, so he should write; and let him who owes the debt dictate, and he should be careful of (his duty to) Allah, his Lord, and not diminish anything from it; but if he who owes the debt is unsound in understanding, or weak, or (if) he is not able to dictate himself, let his guardian dictate with fairness; and call in to witness from among your men two witnesses; but if there are not two men, then one man and two women from among those whom you choose to be witnesses, so that if one of the two errs, the second of the two may remind the other; and the witnesses should not refuse when they are summoned; and be not averse to writing it (whether it is) small or large, with the time of its falling due; this is more equitable in the sight of Allah and assures greater accuracy in testimony, and the nearest (way) that you may not entertain doubts (afterwards), except when it is ready merchandise which you give and take among yourselves from hand to hand, then there is no blame on you in not writing it down; and have witnesses when you barter with one another, and let no harm be done to the scribe or to the witness; and if you do (it) then surely it will be a transgression in you, and be careful of (your duty) to Allah, Allah teaches you, and Allah knows all things.
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.
O ye who believe! When ye contract a debt for a fixed term, record it in writing. Let a scribe record it in writing between you in (terms of) equity. No scribe should refuse to write as Allah hath taught him, so let him write, and let him who incurreth the debt dictate, and let him observe his duty to Allah his Lord, and diminish naught thereof. But if he who oweth the debt is of low understanding, or weak, or unable himself to dictate, then let the guardian of his interests dictate in (terms of) equity. And call to witness, from among your men, two witnesses. And if two men be not (at hand) then a man and two women, of such as ye approve as witnesses, so that if the one erreth (through forgetfulness) the other will remember. And the witnesses must not refuse when they are summoned. Be not averse to writing down (the contract) whether it be small or great, with (record of) the term thereof. That is more equitable in the sight of Allah and more sure for testimony, and the best way of avoiding doubt between you; save only in the case when it is actual merchandise which ye transfer among yourselves from hand to hand. In that case it is no sin for you if ye write it not. And have witnesses when ye sell one to another, and let no harm be done to scribe or witness. If ye do (harm to them) lo! it is a sin in you. Observe your duty to Allah. Allah is teaching you. And Allah is knower of all things.