Whoever purchases food by measure or weight is not permitted to sell it to another person until they have measured or weighed it again [349] - This is the well-known issue of selling food until the measure is completed. Ibn Uthaymeen said: "The food that is subject to measurement includes wheat, barley, dates, raisins, curd, rice, corn, and similar items—essentially, what is edible and measured. If you purchase it, do not sell it until you have measured it. For example, if I bought this pile of grain from the farmer at a price of one dirham per measure, and then someone came to me and said: 'Sell me this wheat that you purchased from so-and-so,' is this permissible? No, until I measure it first, then I can sell it. If I sell it to him and he says: 'Sell it to me and I will measure it on your behalf,' we say: 'This is not valid, and I cannot sell it.' However, it is permissible for me to authorize you to receive it, so you can go and measure it on my behalf. Once you have measured it and completed the measurement [deliver it to me], then I will sell it to you. Now we ask: Can this be analogized to other items, such as selling something by weight? We say: 'Do not sell it until you weigh it.' The answer is: Yes, we say if a person sells something that is weighed, they should not sell it until they have weighed it, because the reason is the same: the possibility of increase or decrease. Additionally, the conditions related to the initial sale have not yet been fulfilled, as there is still something connected to the completion of the first contract, which is the measurement or weighing.     Can this also be applied to items sold by count, such as            = = saying: 'I sold you this apple, each for such-and-such,' or this egg, each for such-and-such, when I have purchased them from so-and-so in quantity? The answer is: Yes, because the reason is the same. And can this be applied to items sold by yard, such as selling you this length of rope, each meter for such-and-such? The answer is: Yes, because it requires measurement." "Fath Dhil Jalal wal Ikram" (3/545).   . This is agreed upon by the four major schools of Islamic jurisprudence [350] - Ibn Hajar said: "Whoever purchases a measure and takes possession of it, then sells it to someone else; it is not permissible for him to deliver it based on the first measurement until he measures it again for the one who purchased it the second time. The majority have stated this." "Fath al-Bari" (4/351). : the Hanafi [351] - "Tabyeen al-Haqaiq" by al-Zaylai (4/81); "Al-Binayah" by al-Ayni (8/359- 360). , Maliki [352] -If he purchased it by measure, it is not permissible to sell it by measure or by estimation until it has been measured. If he purchased it by estimation, he is allowed to sell it immediately upon the contract. "Hashiyat al-Dusuki ala al-Sharh al-Kabir" (3/153);  "Mawahib al-Jalil"  by Ulaysh (5/250); "Al-Fawakih al-Dawani" by al-Nafrawi (2/78). , Shafi'i [353] -"Fath al-Aziz" by al-Rafii (8/190, 450); "Rawdat al-Talibin" by al-Nawawi (3/397); "Mughni al-Muhtaj" by al-Shirbini (2/74). , and Hanbali [354] - The measurable, the weighed, the sown, and the counted; it is not permissible to transact in them before taking possession of them, and possession, according to them, is established by measuring for the measurable, weighing for the weighed, and so on. "Al-Mubdi" by Burhan al-Din Ibn Muflih (4/15) schools, and it is also the opinion of some of the early scholars (salaf) [355] - Ibn al-Mundhir said: "The scholars have differed regarding one who purchases food measured by volume, takes possession of it, and then sells it measured by the same volume he received; a group said: This is not permissible until the two measures are conducted, the measure of the seller and the measure of the buyer. This is the view of Al-Hasan Al-Basri, Muhammad ibn Sirin, Al-Sha'bi, and 'Ata'..." "Al-Awsat" (10/151)).    Al-Khattabi said: "Among those who stated that it is not permissible to sell it using the initial measure until it is measured a second time are Abu Hanifa and his companions, Al-Shafi'i, Ahmad ibn Hanbal, and Ishaq. This is the view of Al-Hasan Al-Basri, Muhammad ibn Sirin, and Al-Sha'bi. Malik said: If he sells it on credit, it is discouraged, but if he sells it for cash, there is no objection to selling it using the initial measure."  ((Ma'alim al-Sunan) (3/137)), and see: "Bidayat al-Mujtahid" by Ibn Rushd (3/224). .
The Evidences:
Firstly: From the Sunnah:
1. On the authority of 'Uthman رضي الله عنه he said: "I used to buy dates from a group of Jews called Banu Qaynuqa' ( (بنو قينقاعand sell them at a profit. This reached the Prophet صلى الله عليه وسلم, who said:  'O 'Uthman, when you buy, measure (the dates), and when you sell, measure (them). [356] - Al-Bukhari reported it as a suspended narration with a weak chain before Hadith (2126) of the raised narration. It was also reported through connected chains by Ibn Majah (2230) similarly, and Ahmad (444) with this wording. Al-Albani authenticated it in "Sahih Sunan Ibn Majah" (2230), and Shu'ayb Al-Arna'ut graded it as good in his verification of "Musnad Ahmad" (444), while Ahmad Shakir authenticated its chain in his verification of "Musnad Ahmad" (1/220). Al-Haythami also graded it as good in "Majma' al-Zawa'id" (4/101). Ibn Hajar stated in his book "Taqreeq al-Taliq" (3/240): "From the totality of these chains, it is known that the Hadith has an original source." '"
2. On the authority of Tawus, from Ibn 'Abbas رضي الله عنهما he said: The Messenger of Allah صلى الله عليه وسلم said: "Whoever purchases food should not sell it until he has measured it... [357] - Narrated by Muslim (1525). "
Reasoning (from the Two Hadiths):
Both hadiths indicate that whoever buys food by measure or weight is not permitted to sell it to another until they have measured or weighed it again [358] -See: Al-Sail Al-Jarrar by Al-Shawkani (p. 503); "Fath Dhil Jalaal Wal Ikram" by Ibn Uthaymeen (3/545). .
Secondly: The act of delivery (in handing over the goods) occurs twice in these transactions, and one of the conditions for its validity is measuring or weighing, so this requires the process to be repeated [359] -See: "Mughni al-Muhtaj "by Al-Sharbini (2/74). .
Thirdly: Because both parties are entitled to receive their due portion through proper measurement, and there could be discrepancies between two measures, thus relying solely on the first measure is not permissible [360] -See: "Mughni al-Muhtaj "by Al-Sharbini (2/74). .
Fourthly: Due to the possibility of error in the first measurement; it could be deficient or excessive, resulting in the impermissible use of another's property [361] - See: Majma' Al-Anhur (2/80). .