If a person sold something to someone saying ‘you won't find this cheaper anywhere else’, whereas the seller knew that he was lying and the same product was actually being sold cheaper in other places, what would be the ruling with regards to the money earned?
بِسْمِ اللهِ الرَّحْمنِ الرَّحِيْم
In the name of Allah, the Most Gracious, the Most Merciful
There are many ahadith regarding the honesty of a businessman and the merits of doing an honest business. One of which is that the Prophet, peace, and blessing be upon him, said that an honest and trustworthy merchant will be [raised] with the Prophets, the truthful and the martyrs (Tirmidhi 1209).
In another hadith, the Prophet, peace, and blessing be upon him, has reported about one who has taken false oaths for business: "There are three whom Allah will not look at on the Day of Judgement, nor will He purify them, and theirs is a painful punishment." We said: "Who are they O Messenger of Allah? For they have indeed failed and are lost!" He said: "The Mannan, the one whose Izar hangs (below the ankles) and the one who promotes his merchandise with a false oath. (Tirmidhi 1211)”
Keeping these narrations in mind, the money would be permissible as no oath was taken. It is best to keep all transactions and business far away from false marketing or cheating.
Only Allah knows best
Written by Maulana Shadman Ahmed
Checked and approved by Mufti Mohammed Tosir Miah
Darul Ifta Birmingham