[Machine] The Prophet ﷺ prohibited the sale of uncertain items, because during the Pre-Islamic era, they used to sell the ropes of a camel predestined for slaughter. The Prophet ﷺ forbade such practice.
نَهَى رَسُولُ اللهِ ﷺ عَنْ بَيْعِ الْغَرَرِ وَذَلِكَ أَنَّ الْجَاهِلِيَّةَ كَانُوا يَتَبَايَعُونَ بِالشَّارِفِ حَبَلَ الْحَبَلَةِ فَنَهَى رَسُولُاللهِ ﷺ عَنْ ذَلِكَ