如果我们考察世界市场上存在的金融性质的贸易合同，会发现买卖交易分为六种类型：

If we examine the trade contracts of a financial nature that exist in world markets, we would find that purchase and sales transactions occur in six types:

1. 同种货币之间的兑换，例如用旧版伊拉克第纳尔纸币兑换新版纸币。

1. The exchange of a currency with the same type of currency, such as the exchange of old Iraqi dinar notes for new notes.

2. 一种货币与另一种货币的兑换，例如埃及镑兑换美元。

2. The exchange of one currency for another currency, such as the exchange of Egyptian pounds for dollars.

3. 以某种货币购买某些商品，并在同一笔交易中用另一种货币购买该货币，例如用美元购买飞机，并将这些美元兑换成伊拉克第纳尔。

3. The purchase of certain goods with a certain currency and the purchase of that currency with another currency, such as the purchase of aircraft with dollars and the exchange of those dollars for Iraqi dinars in one single deal.

4. 以英镑出售某些商品，然后再将其兑换为美元。

4. The sale of certain goods in sterling and then exchanging them for dollars.

5. 以某种货币出售某些债券。

5. The sale of certain bonds with a certain currency.

6. 出售某家公司的股票，并以某种货币进行交易。

6. The sale of stocks in a certain company, with a certain currency.

这六项交易都是具有金融性质的贸易合同。至于债券和股票的买卖,按照伊斯兰教法规定,是绝对禁止的:债券有固定的利率,因此其中存在高利贷,这本身就是一种高利贷交易。股票代表对某公司的部分所有权,而该公司的业务本身在根本上是不合法的,因此买卖股票是被禁止的。同样,交易所有公众公司的股票也是被禁止的,无论这些公司经营的是合法贸易,例如工业和商业类公众公司,还是经营非法业务,例如银行类公司的股票。至于以某种货币购买货物、将该货币兑换成另一种货币,或者出售某些货物以换取某种货币、再将该货币兑换成另一种货币,这些都属于两项交易:一项是买卖交易,一项是兑换交易。因此,它们遵循买卖和兑换的规则,并应受分离交易规则(即交易双方须在交易会场分离前完成交割)的约束。

These six transactions are trade contracts of a financial nature. As for the purchase and the sale of bonds and shares, this is categorically forbidden under the Shari’ah rules, for the bonds have a determined rate of interest thus usury occurs in them; it is even in itself, a usurious transaction. A stock represents a part ownership in a company that is unlawful in the first instance, thus trading in stock is forbidden, and it is also forbidden to deal in the stock of all the public companies, whether these were companies that deal in lawful trade, such as the industrial and commercial public companies, or companies that deal with unlawful trade such as the banks’ stocks. As for the purchase of goods with a certain currency, the exchange of that currency for another, or the sale of certain goods for certain currency and then exchanging that currency for another currency; these represent two transactions, a transaction of purchase and sale and a transaction of exchange. Therefore, they follow the rules of trading and exchange, and they should be subject to the rule of the separation of the deals.

同一种货币与相同或不同的货币进行交换，属于兑换交易，是被允许的。这是因为兑换就是以钱换钱，以金换金、以银换银，同类相等地交换，或异类相互交换，且数量相等。兑换所针对的是货币本身，正如它适用于金银一样，因为货币的特性是以金银的货币价值为依据的。所以货币并不是与金银同类的物品，而是金银的一种形式。 因此，如果有人用银来购买金，一个金币换一个银币，比如说："我把这枚金第纳尔卖给你，换这些银迪尔汗。"在交易时当场指明它们；或者，他在不在场的情况下，以描述的货币物品签订合同，比如说："我把这些埃及镑卖给你，换十枚希贾兹迪尔汗。"这些例子都是被允许的，因为合同中通过指明货币而确定了它们，从而确立了对其资产的所有权。因此，用金换银是被允许的，无论是镑换迪尔汗，还是银饰，或是银屑（即Niqar）。Niqar是金屑（即Tibr）的银质对应物。用银换金也是被允许的，无论是首饰、金条还是金屑。但所有此类交易都必须当场进行、且双方须有明确描述，无论是等量还是不等量，按重量对重量，或按已知数量对已知数量（Jizaf），或以重量换已知数量，前提是所交换的属于两种不同的类别。若属于同一类别，则只能等量交换，不得不等。金换金也是被允许的，无论是第纳尔、首饰、金条还是金矿石，只要按重量对重量、对已描述的物品、当场交割，原则上不允许有任何区别。 银币也可以与银币交换，无论是迪尔汗（Dirham）、首饰还是尼卡尔（Niqar），都必须按重量相等，且须是已知的同类物品对同类物品，当场即时交付（手对手），原则上不允许有任何差额。因此，同类货币之间的交换是允许的，前提是数量相等、当场交付，并且是已知的同类物品对同类物品。不同货币之间的交换也是允许的，在这种情况下，数量相等与否的条件不适用，但必须当场交付，并且是已知的同类物品对同类物品。 关于交换许可的依据，有以下圣训。提尔米兹（At-Tirmidhi）转述乌巴德·伊本·萨米特（Ubada ibn As-Samit）的话说：真主的使者ﷺ说：“你们可以随意以金换银，但须当场交付。” 穆斯林（Muslim）也转述乌巴德·伊本·萨米特的话说：“我听到真主的使者ﷺ禁止以金换金、以银换银、以小麦换小麦、以大麦换大麦、以枣换枣、以盐换盐，除非数量相等且是已知的同类物品对同类物品。谁增加或索取增加，谁就陷入了高利（Riba）。” 穆斯林还转述艾布·巴克拉（Abu Bakra）的话说：“他ﷺ命令我们可以随意以银买金，也可以随意以金买银。有人问他ﷺ，他ﷺ便说：‘手对手。’”他又补充道：“我就是这样听来的。” 提尔米兹转述马立克·伊本·奥斯·阿尔-哈达until（Malik Ibn Aws Al-Hadathan）的话说：“我前来询问谁可以兑换一些迪尔汗。当时塔勒哈·伊本·乌拜杜拉（Talha Ibn Ubaydullah）正与欧麦尔·伊本·哈塔卜（Umar ibn al-Khattab）坐在一起，他说：‘让我们看看你的金子，然后稍后再来找我们，等我们的仆人来时，我们会把你的银子（迪尔汗）交给你。’” 于是欧麦尔说:“不,以真主发誓,你必须把他的银币还给他,或把他的金子归还,因为真主的使者ﷺ说:‘银换金含有利息(里巴),除非是当面交割;小麦换小麦是里巴,除非当面交割;大麦换大麦也是里巴,除非当面交割;枣换枣也是里巴,除非当面交割。’”因此,金换银除非当面交割,否则是被禁止的。如果交易双方在当面交割之前分开,这笔交换就是非法的。布哈里和艾布·达乌德转述,欧麦尔传述真主的使者ﷺ说:“金换银是里巴,除非当面交割。”交易双方必须在交易地点即时交割,因为如果他们在交割之前分开,这笔买卖就不能合法地被视为已经完成。这是因为交换是价格之间的相互交易,而在交易地点即时交割是交换有效的首要条件。布哈里转述,马立克·伊本·奥斯说:真主的使者ﷺ说:“金换银是里巴,除非是当面交割。”提尔米兹也转述,真主的使者ﷺ说:“你们可以随意金换银,只要是当面交割。”真主的使者ﷺ禁止延期交易的金银互换,也禁止以不在场的资产交换在场的资产。因此,交换必须在交易地点进行;如果交易双方在交割之前分开,由于未满足其主要条件之一,这笔交换就是无效的。 但如果交易的一部分在交易地点已经交割,那么交易对已交割的部分及其对应的对价是有效的,而对交易的其余部分及其对应部分则无效。这是因为允许将交易分割为若干部分。例如,某人用一第纳尔与一个只有五个迪拉姆的人交换十个迪拉姆,那么在十个迪拉姆全部交割之前就分开,对他们来说是无效的。如果五个迪拉姆已经交割,然后他们分开,那么这笔交换对一半的第纳尔无效,而对另一半有效,即与已交割的五个迪拉姆相当的那一半。这是因为允许分割买卖交易。如果持有五个迪拉姆的人为完成交易,从对方或第三方借入余下的钱款,那么交换是有效的,前提是借款不是交易的条件;如果借款是交易的条件,那么交易就无效。

The sale of one currency for the same or a different currency is a transaction of exchange, and it is permitted. This is because exchange is the swapping of money for money, of gold and silver, either equally in the same type, or differently and equally in the different types. The exchange takes place in the money as it takes place in gold and silver, for the description of gold and silver applies to it in its quality as a currency. Money is not analogous to gold and silver but is one of its forms, for it is based on either of them in their monetary valuation. So if a person were to purchase gold for silver, coin for coin, by saying for instance: “I sold to you this golden Dinar for these silver Dirhams”, by naming them while present at the time of sale, or if He were to purchase gold for silver while not present such as when signing a contract over a described monetary item while not being present, and He says: “I sold to you these Egyptian pounds for ten Hijazi Dirhams”. These examples are permitted, for the monies are determined in the contracts by naming them, thus the ownership of their assets is established. Therefore, trading gold for silver is permitted, whether this was pounds for Dirhams, silver jewellery or for Niqar (i.e. silver dust). The Niqar is the silver equivalent of Tibr (i.e. gold dust). It is also permitted to trade silver for gold, whether jewellery, bullion or gold dust. However, all such trade must be conducted hand to hand and described, either equally or unequally, weight for weight, or known quantity (Jizaf) for known quantity, or weight for known quantity in all the mentioned types, provided the exchange is in two different types, for if they were from the same type, they can only be equal and must not be unequal. Gold could be traded for gold, whether this were Dinars, jewellery, bullion, ore, weight for weight, described asset for described asset, hand to hand, and in principle no difference is permitted. Silver could also be traded for silver, be it Dirhams, jewellery or Niqar, weight for weight, described asset for a described asset, hand to hand, and no difference is allowed in principle. Therefore, the exchange between the same type of currency is permitted, provided that it is equal, hand to hand and a described asset for a described asset. The exchange between two different currencies is also permitted and in this case, the condition of equality and disparity does not apply, but this must be exchanged hand to hand, and a described asset for a described asset. Evidence for the permissibility of exchange is derived from the Hadith reported by At-Tirmidhi on the authority of Ubada ibn As-Samit who said that the Messenger of Allah (pbuh) said: “You may trade gold for silver as you wish, hand to hand.” Muslim also reported on the authority of Ubada ibn as-Samit who said: “I heard the Messenger of Allah (pbuh) forbid the trading of gold for gold, silver for silver, wheat for wheat, barley for barley, dates for dates, salt for salt, unless this was in equal quantities and described asset for a described asset. He who increases or takes an increase would fall into usury (Riba).” Muslim also reported on the authority of Abu Bakra who said: “He has ordered us to buy gold for silver as we wished, and to buy silver for gold as we wished. A man asked Him (pbuh) so He said: “Hand to hand”. He added: “That is how I heard it.” At-Tirmidhi reported on the authority of Malik Ibn Aws Al-Hadathan who said: “I came asking who would exchange some Dirhams, whereupon Talha Ibn Ubaydullah as He was sitting with Umar ibn al-Khattab, said: ‘Show us your gold,’ and then come to us at a later time, when our servant would come we would give you your silver (Dirhams).” Upon this Umar said: “No by Allah, you shall give Him his silver coins or return his gold to him, for the Messenger of Allah (pbuh) said: ‘Exchange of silver for gold has an element of Riba in it unless it is exchanged hand to hand, wheat for wheat is Riba unless it is hand to hand, barley for barley is also Riba unless it is exchanged hand to hand and dates for dates is also Riba unless it is hand to hand.”’ It is therefore forbidden to trade gold for silver except hand to hand, for if the two trading parties parted company before they exchanged hand to hand, the exchange would be unlawful. Bukhari and Abu Dawud reported on the authority of Umar that the Messenger of Allah (pbuh) said: “Exchanging gold for silver is riba except hand to hand.” It is conditional that the two contracting parties cash in at the place of the deal, for once they separated prior to the cashing in, the sale would not lawfully be considered to have taken place. This is because the exchange is the inter-trading of prices, and to cash in at the place of the deal is a prime condition for the exchange to be valid. Bukhari reported on the authority of Malik Ibn Aws who said: The Messenger of Allah (pbuh) said: “Trading gold for silver is Riba unless it is hand to hand.” At- Tirmidhi also reported that the Messenger of Allah (pbuh) said: “Trade gold for silver as you wish, as long as it is hand to hand.” The Messenger of Allah (pbuh) prohibited the trading of gold for silver in credit, and also prohibited the trading of an absent asset for a present one. Therefore, the exchange must take place at the place of the deal, for if the contracting parties separated before cashing in, the exchange would be invalid due to the non-fulfilment of one of its main conditions. If however, part of the deal was exchanged at the place of the deal, the deal would then be valid in the part which was exchanged and, its equivalent on the recompense and it would be invalid for the remainder of the deal and its equivalent part of the deal. This is because it is permitted to divide the deal into parts. For instance, if a person exchanged one Dinar for ten Dirhams with a person who has only five Dirhams, it would be invalid for them to separate before the full ten Dirhams are cashed in. If the five Dirhams were cashed in and they separated, the exchange would be invalid for half the Dinars and valid for the other half which is equivalent to the five Dirhams that have been cashed in. This is because it is permitted to divide the deal of sale. If the person with the five Dirhams borrowed the remainder of the money from the other person or a third party, to complete the deal, the exchange would be valid, as long as the borrowing was not a condition in the deal, for if it was a condition in the deal, the deal would be invalid.