出售自己不拥有的东西，以及尚未完成所有权转移的东西，是被禁止的，这是因为有关此事的圣训。这些圣训具有普遍性，涵盖了所有对不拥有或所有权尚未完成之物的买卖。先知ﷺ说道：

Selling that which one does not own and that whose ownership has not been accomplished is forbidden due to the ahadith concerning that. The ahadith came generally including all sales of that which is not owned or whose ownership is not completed. He (saw) said:

他对欧泰卜·本·尤赛德说:

And he said to Uttab bin Usayd:

然而，这些一般性的证据在预付款买卖之外另有限定。至于预付款买卖（salam），沙里阿已将其排除在禁令之外并予以允许。他ﷺ说：

However these general evidences have been specified in other than the sale of advance credit. As for advance credit sale, the Shar’a has excluded it from the prohibition and permitted it. He (saw) said:

“سلم”与“سلف”在词形和意义上相同，都读作两个“فتحة”。它指的是：一方以预付的现金作为对价，交付在一段时间后才拥有的、已描述的货物，期限明确。预付款赊购销售是一类买卖，其缔约方式依照买卖的缔约方式，并以“سلم”和“سلف”之名订立。也有人说“أسلم”和“أسلف”。其条件与买卖相同。人们之间的“سلم”与“تسليف”交易之所以发生，是因为人们有这方面的需要，尤其是农民和商人。农作物和果实的所有者需要为自己和为作物的生长开支，以完成这些作物和果实所需的工作。他们可能手头缺钱，于是在作物和果实尚未长成时就将其出售，以预付价格成交，并在缔约会场（مجلس العقد）上当即收取价款，条件是待约定期限届满时将货物交付买方。商人也会以约定的期限出售他们并不持有的货物，并在缔约会场上当即收取价款，条件是待约定期限届满时交付货物。

The “salam” is the “salaf” with two “fatha” in weight and meaning. It is the one who delivers present compensation for a described compensation as surety for a period i.e. advance money as price for a good he will possess after a time for a specific period. The advance credit sale is a category of sale which is contracted according to what a sale is contracted, and by the word “salam” and “salaf”. And it is (also) said “aslam” and “aslaf”. The same conditions are considered as in a sale. The transaction of people in salam and tasleef takes place because they are in need of it particularly the farmers and traders. The owners of crops and fruits need expenditure for themselves and upon it to complete what these crops and fruits require of work. Money could become scarce such that they do not have it, so they sell their produce before it emerges for an advance price which he takes possession of immediately in the contract session (majlis al-‘aqd) upon the condition of delivering the good to the buyer when the imposed period falls due. The trader would sell the goods not with them for a specific period which they would determine, and they take possession of the price immediately in the contract session upon condition of delivering the good when the imposed period becomes due.

预付款购买的赊销（预售信用交易）是否允许，有圣训为据。据伊本·阿拔斯（愿真主喜悦他）的传述，他说：

The permissibility of advance credit sale is established by the Sunnah. It is narrated from ibn Abbas (ra) who said:

来自阿卜杜勒-拉赫曼·本·阿布扎和阿卜杜拉·本·阿布·奥法，二人都说：

From Abdurahman bin Abza and Abdullah bin Abi Awfa who both said:

在一段圣训中：

And in a narration:

所有这些都是允许预付款赊购的明确证据。至于哪些东西可以进行预付买卖（萨拉姆），哪些不允许，这在圣训和穆斯林学者的一致意见（Ijma'）中是明确的。这是因为萨拉姆是买入并不拥有之物，以及买入所有权尚未完成之物，而这两者都是被禁止的。萨拉姆因明确的经文而被排除在此禁令之外，因此禁令的界限就限定在其他情况中。据此，必须明确指出萨拉姆有效的物品范围。回到经文中我们可以发现，凡是可以用量器或衡器计量的物品，以及可以计数的物品，萨拉姆都是允许的。至于允许用于可计量和可称重之物，这是基于伊本·阿拔斯的圣训所确立的依据。安拉的使者ﷺ说：

All these are clear evidences for permitting advance credit sale. As for what are the things in which salam is allowed, and what are the things in which it is not permitted, this is clear in the hadith and Ijma’a. This is because the salam is buying that which is not owned and buying something over which ownership has not been completed, and they are both prohibited. Salam was excluded for them by a clear text so it specified the prohibition in other than that. Accordingly it is necessary that the thing in which salam is valid be clearly stated. Upon returning to the texts we find that Salam is permitted in everything that is measured and weighed just as it is permitted in everything counted. As for permitting it in what is measured and weighed, this is due to what is established in the hadith of ibn Abbas. The Messenger of Allah (saw) said:

在伊本·阿拔斯的另一则圣训中，他说：安拉的使者(SWT)说： Wait — the rules say to keep (SWT) only as is and to write ﷺ after mentions of the Prophet Muhammad. Here "(saw)" is an abbreviated honorific for the Prophet, so it must be replaced with ﷺ, and "the Messenger of Allah" is the Prophet, so ﷺ follows it. The corrected translation: 在伊本·阿拔斯的另一则圣训中，他说：安拉的使者ﷺ说：

And in another narration of ibn Abbas who said: The Messenger of Allah (saw) said:

这表明所交付的款项是以计量和称重为准的。至于以计数计算之物的许可性，学者们一致同意以食物进行萨拉姆（预付定购）是被允许的。这一公议由伊本·孟祚尔转述。布哈里记录并说：舒अ巴向我们讲述，他说：穆罕默德或阿卜杜拉·本·阿比·阿勒-马贾利德告诉我们，他说：

This indicates that the money which is delivered is in what is measured and weighted. As for its permissibility in the counted (things), the Ijma’a has contracted upon the Salam in foodstuff being allowed. This Ijma’a has been transmitted by ibn Mundhir. Al-Bukhari narrated and said: Shu’bah related to us and said: Muhammad or Abdullah bin Abi Al-Majalid informed and said:

这表明食品是被允许的。食品并非不可衡量、称重或计数,因此该规定适用于所有可以被衡量、称重或计数的食品,正如收取(占有)的规定适用于其中需要收取的部分,也正如它适用于过量的利息(riba al-fadhl):若在量度、重量或数目上有超出,便构成利息。因此,预付款买卖(salam)同样适用于那些可以被衡量、称重和计数的食品。圣训中有关于可衡量与可计数之物允许的经文,但未提及可计数之物。关于食品允许性的公议(ijma‘)使可计数之物也被纳入预付款买卖之中。

This indicates that foodstuff is permitted. Foodstuff is not devoid of being measured, weighed or counted so the rule is related to all that foodstuff which is measured, weighed or counted just like taking possession is related to it in its being of that which needs taking possession of and just as it is related to riba of excess (riba al-fadhl) in its being riba if there is excess in the measure or weight or count. So salam is also related to it in its being foodstuff which is measured, weighed and counted. In the hadith is a text upon the permissibility of the measured and the counted but it did not mention the counted (thing). The Ijma’a over the permissibility of foodstuff makes the counted (thing) included in the Salam.

然而，预付款项所购之物必须描述精确，例如哈瓦兰小麦（Jurani wheat）、比尔尼枣（Birni dates）、埃及棉、印度丝绸、土耳其无花果；在计量或称重上也必须精确，例如叙利亚的沙阿（sa’a）、伊拉克的磅、公斤和升。也就是说，必须明确并描述所用的计量单位或重量。

However it is necessary that the things paid for in advance are exact in description like Jurani wheat, Birni dates, Egyptian cotton, Indian silk, Turkish figs and exact in measurement or weight like a Syrian sa’a, an Iraqi pound and the kilo and litre i.e. it is necessary that the measure or weight be known and described.

正如预付款所针对的类别必须是已知的，同样，买卖必须有一段时间，并且这段时间必须是已知的。萨拉姆（预付买卖）不能立即成立，而必须将期限作为条件，这是因为先知ﷺ的话语：

Just as it is obligatory for the category for which the advance is paid be known, similarly the sale must be for a period and it must be a known period. Salam is not valid immediately, but rather it is necessary that the period be made a condition due to the Prophet (saw)’s statement:

这表明期限是萨拉姆（预付定金买卖）有效的条件之一。然而，如果是立即交付且未确定期限，则不称为预付买卖，因为使其成为萨拉姆和赛拉夫的，是将两项对价中的一项提前、另一项延后。根据先知（愿主赐福他并使他平安）的话“以已知的期限”，期限必须是已知的。规定期限只适用于本身没有差异的期限，例如一个月、一年、六个月，或某个具体日期，且该日期不会有很大差别，如宰牲节或斋月。同样，以基督徒的复活节及其斋期为萨拉姆的期限也是有效的，因为这是已知的且没有差异。微小的差异是可以原谅的。任何期限都可以延后，无论是近期还是远期，都没有分歧。然而，“期限”（ajal）一词有其所指，应依据人们对其所指的习惯用语来处理。如果他们认为其中不包括一小时，而它属于立即交付的类型；如果他们认为一小时也算一个期限，那么一小时就如同一年一样被视为期限。

This indicates that the period is a condition for the validity of salam. However where it is immediate and no period is determined then it is not called advance credit sale because that which makes it Salam and salaf is the bringing forward of one of the compensations and delaying the other. It is necessary that the period be known due to the Prophet (saw)’s statement: “for a known period.” Specifying the period is only for a period which in itself does not differ such as a month, year, six months or to such and such date in a way that there is no great difference over it like Eid al-Adha or to Ramadhan. Similarly it is valid that the salam be for the Easter of the Christians and their fasting as this is known and does not differ. A minor difference is forgiven. Every period is allowed to be delayed until without difference between a nearby or a remote period. However the word “period” (ajal) has an indication which is acted upon according to the terminology of the people over its indication. If they consider that an hour is not considered therein but rather it is from the type of immediate (sale), and if they consider it a period thereupon the hour is considered a period like the year is considered a period.

同样，由于先知（ﷺ）的话：“那么让他预先按已知的价格支付。”价格必须是已知的，这是必要的。除非在订立合同的当场立即交付价款，否则是不允许的。因此，如果缔约双方在全部价款被接收之前分开，那么整个合同即告无效。这是因为，在先知（ﷺ）用来对我们说话的阿拉伯语中，预付买卖（salam）指的是以某物预先换取某物，即先付款，后取得货物。所以，如果一个人没有为他预先订购的货物付款，那么他就没有预付任何东西，他只是承诺将要预付。如果他支付了部分价款，无论多少，那么预付买卖在他已付款的部分有效，在他未付款的部分无效。卖方从买方处接收价款，是预付买卖有效的条件。至于买卖时货物是否存在，则不是条件。预付买卖在订立合同时，无论标的物是现有的还是不在场的，无论对方是拥有货物的人还是没有任何货物的人，都是允许的。这是因为，先知（ﷺ）来到麦地那时，人们会为一年或两年的水果预付款项。众所周知，水果在这段时间内并不会一直存在，而先知（ﷺ）并没有禁止他们预付一年或两年的款项，反而认可了这种做法。因此，在约定的一段期限之后交付货物，无论货物当时是否存在，预先支付货物的价款都是允许的。然而，价款中不得有过度的欺诈；相反，价格必须依照订立合同时的市场行情而定，其参照的是延期的期限，而不是货物的交付。这是因为，预付买卖也是一种买卖，而一切买卖中过度的欺诈都是被禁止的，所以预付买卖也包括在内。 正如以即时交付的货物换取延期价款时存在过度欺诈是禁止的,同样,以未来交付的货物换取即时交付的价款时存在过度欺诈也是不被允许的,因此萨拉姆(预付定购)中的欺诈是haram(非法)的。若萨拉姆中出现欺诈,其规则与买卖中的欺诈规则相同;对于受骗者,有选择权。若他愿意,可以撤销买卖;若他愿意,也可以执行买卖。他无权取得真实货物的价格与其所购价格之间的差额。然而,此选择权须满足两个条件:第一,订约时不知情;第二,欺诈性的溢价或减价是人们通常不会受骗的程度。明显的欺诈由商人的评判来衡定,他们认为是欺诈的便发展为欺诈,而他们不认为是欺诈的,则不构成欺诈。

Similarly it is necessary that the price be known due to his (saw) statement: “Then let him pay in advance for a known price.” It is not permitted except that the price be handed over immediately in the contract session, so if the contractors separate before the entire price is taken possession, then the whole contract is invalidated. This is because advance sale in the Arabic language with which the Messenger of Allah (saw) addressed us is something being given for something i.e.. Money is given in advance for a good taken afterwards. So if one does not pay for what he ordered in advance (aslaf) then he has not paid in advance for anything; he has merely promised that he will pay in advance. Were he to pay some of the price, whether a little or most of it, then the advance sale is valid in what he gave possession of and void in what he did not give possession of. The seller taking possession of the price from the buyer is a condition for the validity of Salam. As for the existence of the sold good during the sale, it is not a condition. Salam is permitted in what is present and what is not present when the Salam is contracted, and with the one who has something with him and the one without anything. This is because the Prophet came to Madinah; they would pay in advance for fruits for a year or two. It is known that fruits do not remain for this period and the Messenger did not prohibit them from one year or two but rather consented upon that for them. Hence it is permitted to pay the price of the good to be delivered after a specific period considered a period, whether the good exists or not. However it is a condition that there should not be in the price excessive fraud; rather it is obligatory that the price be according to the market during the sale contract similar to the deferred period, not the delivery of the good. This is because the Salam is a sale and excessive fraud is forbidden in all sales so the Salam in included within it. Just as it is haram for a good to be taken possession of immediately for a deferred price via excessive fraud, similarly it is not permitted to sell a good to be taken possession of in the future for a price to be taken possession of immediately via excessive fraud, therefore fraud in salam is haram. If fraud appears in the Salam then its rule is the rule of fraud in sale; for the deceived, there is an option. If he wishes, he can annul the sale and if he wishes he can execute it. It is not for him to take the difference between the price of the real good and the price with which it is bought. However this option is established upon two conditions. Firstly, the absence of knowledge at the time of the contract. Secondly, the deceitful surplus or deficit which the people are not deceived with. Clear fraud is evaluated by the evaluation of the trader so what they consider is fraud develops into and what they do not, is not