The second reason is that the jars of Hajar were the largest of the jars and the most well-known during the era of the Prophet (may the peace and blessings of Allah be upon him). Al-Khattabi mentioned this, saying: "They are of a well-known manufacture and a known capacity. They do not vary, just as the sa' measures and dry measures do not vary, because a legal limit cannot be established upon something unknown." Abu 'Ubayd said: "They are the hiban (earthen jars), and they are widely known and recognized, so the term 'two qullahs' should be interpreted based upon them due to their fame and size. For any countable item set as a singular measure refers only to the largest of its type, as it is closer to certainty and fewer in number. For this reason, the zakat threshold was established based on the awsuq (loads), not the aswu' (sa's) or the amdad (mudds)."
This issue clearly indicates by its explicit wording that if water reaches the amount of two qullahs and does not change due to impurities falling into it, it does not become impure. Its implied meaning indicates that if water changes due to impurity, it becomes impure even if it is a large quantity, and that water less than two qullahs becomes impure merely by contact with impurity, even if it does not change.
As for the impurity of water that has changed due to impurity, there is no disagreement regarding it. Ibn al-Mundhir said: "The people of knowledge have reached a consensus that if a small or large amount of water has an impurity fall into it, and it changes the water's taste, color, or odor, it is impure as long as it remains in that state." Abu Umamah al-Bahili reported that the Prophet (may the peace and blessings of Allah be upon him) said: "Water is pure; nothing makes it impure except that which overcomes its odor, taste, or color." Narrated by Ibn Majah (17). Harb ibn Isma'il said: Ahmad was asked about water if its taste or odor changes (18). He replied: "One should not perform ablution with it nor drink it, and there is no hadith regarding it. However, Allah the Exalted has forbidden carrion, so if carrion is in water and its taste or odor changes, that is the taste and odor of the carrion."
(11) In [manuscript] M: "And because". (12) Al-hubb (with a damma): the large earthen jar. It is an Arabized Persian word. Its plural is hiban (with a kasra) and hubaba, following the pattern of 'anaba. (13) In M: "was made". And qulida means "was established" or "was collected". See: Al-Qamus. (14) Plural of wasq, which is a camel load, or sixty sa's according to the sa' of the Prophet (may the peace and blessings of Allah be upon him). (15) The sa': a dry measure. The sa' of the Prophet (may the peace and blessings of Allah be upon him), which was in Medina, is four mudds. (16) The mudd: a dry measure. According to the people of the Hijaz, it is one and one-third ratls. (17) In: The Book of Basins, from the Book of Purification and its Sunan. Sunan Ibn Majah 1/174. (18) In M: "and its odor".
والثانى، أنَّ قلالَ هَجَرَ أكبرُ ما يكونُ مِن القِلالِ، وأشْهرُها في عَصْرِ النبيِّ -صلى اللَّه عليه وسلم-، ذكَره الْخَطَّابِىُّ، قال: وهى مشهورةُ الصَّنْعةِ، معلومةُ المِقْدار. لا تَختلفُ كما لا تختلف الصِّيعانُ والْمَكايِيل، لأن (١١) الحَدَّ لا يقَعُ بالمجهول. وقال أبو عُبَيْد: هي الحِبابُ (١٢)، وهى مُسْتفيضةٌ معروفة، فينْبغِى أن يُحْمَلَ لفظُ القُلَّتَيْن عليها؛ لشُهْرتها وكِبَرها، فإنَّ كلَّ معدودٍ جُعِلَ مِقْدارًا واحدا لم يتناوَلْ إلَّا أكْبرَها، لأنها أَقربُ إلى العِلْمِ، وأقلُّ في العَدَدِ، ولذلك قُلِدَ (١٣) نِصابُ الزَّكاةِ بالأَوْسُقِ (١٤)، دون الآصُعِ (١٥) والأمْدَادِ (١٦).
وقد دَلَّتْ هذه المسألةُ بصَريحها على أنَّ ما بلغ القُلَّتَيْن فلم يتغَيَّرْ بما وقَع فيه لا يَنْجسُ، وبمَفْهُومِها على أَنَّ مَا تغيَّر بالنجاسةِ نَجُسَ وإن كَثُرَ، وأنَّ ما دون القُلَّتَيْن ينْجُس بمُجَرَّدِ مُلاقاةِ النجاسةِ، وإن لم يتغَيَّرْ.
فأما نجَاسةُ ما تغيَّرَ بالنَّجاسةِ فلا خلافَ فيه، قال ابنُ المُنْذِر: أجْمَعَ أهلُ العِلْمِ على أنَّ الماءَ القليلَ والكثيرَ، إذا وقعتْ فيه نجَاسةٌ فغيَّرتْ للماءِ طَعْمًا أو لَوْنًا أو رائحةً، أنه نَجِسٌ ما دام كذلك. وقد روى أبو أُمامةَ الباهِلىُّ، أن النبيَّ -صلى اللَّه عليه وسلم- قال: "الْمَاءُ طَهُورٌ لَا يُنَجِّسُهُ شَىْءٌ إِلَّا مَا غَلَبَ عَلَى رِيحِهِ وَطَعْمِهِ وَلَوْنِهِ" روَاه ابنُ ماجَه (١٧). وقال حَرْبُ بن إسماعيل: سُئِل أحمدُ عن الماءِ إذا تغيَّر طَعْمُه أو رِيحُه (١٨)، قال: لا يتوَضَّأُ به ولا يَشْرَب، وليس فيه حديثٌ، ولكنَّ اللهَ تعالى حَرَّم المَيْتَة، فإذا صارتِ الميتةُ فى الماءِ فتغيَّر طَعْمُه أو رِيحهُ، فذلك طعمُ الميتةِ ورِيحُها،
(١١) في م: "ولأن".(١٢) الحب، بالضم: الخابية. فارسى معرب، وجمعه حباب، بالكسر، وحببة، وزان عنبة.(١٣) في م: "جعل". وقُلِد بمعنى جُمِع. انظر القاموس.(١٤) جمع الوسق، وهو حمل بعير، أو ستون صاعا بصاع النبي -صلى اللَّه عليه وسلم-.(١٥) الصاع: مكيال، وصاع النبي -صلى اللَّه عليه وسلم- الذي بالمدينة أربعة أمداد.(١٦) المد: كيل، وهو رطل وثلث عند أهل الحجاز.(١٧) في: باب الحياض، من كتاب الطهارة وسننها. سنن ابن ماجه ١/ ١٧٤.(١٨) في م: "وريحه".
