Explanation of the Book of Sales-14

The Shaykh : The Shaykh said: "And from Ibn 'Umar (may Allah be pleased with them both), he said:

A man told Allah's Messenger (ﷺ) that he was being deceived (cheated) in business transactions, and he replied, "When you make a purchase say, 'Deceiving (cheating) is not allowed (i.e. he has the choice to return the goods if he wills).'"

ذكر رجل للنبي صلى الله عليه وسلم أنه يُخدع في البيوع ، فقال : إذا بايعت فقل : لا خِلابة

Bulugh al-Maram 7:61

Agreed upon by al-Bukhari and Muslim":
This is a man who was deceived in sales by a deception that was hidden from him but not from others, because deception is of two types: general deception and specific deception, as will come if Allah wills.
And his saying: By what is he deceived? It is possible that he is deceived regarding the merchandise, where it is shown to him as good while it is bad, or there is a defect in it and he does not know the defects, or he is deceived regarding the price and it is increased for him. The important thing is that he is deceived in everything that counts as deception, and the hadith is general.
So the Prophet (peace and blessings be upon him) guided him to get rid of this deception by saying: : And this includes "if you conclude a sale" whether he is the seller or the buyer, so say: No deception, meaning: no deception, meaning: no deception. So when he sold, he would say: , and if the deception became apparent, the contract was annulled. It was mentioned that he used to say: No deception, no deception, meaning that his tongue was thick in this matter. And what concerns us is not that; the important thing is the meaning, which is that he used to say when he concluded a sale: No deception, and if it became apparent that he was deceived, the contract was annulled.