Hadith 10.2
Business Transactions
Jabir said he intended to go to Khaibar, so he went to the Prophet, gave him a salutation and told him of his purpose. He replied, “When you come to my agent take fifteen camel-loads from him, and if he desires a sign from you put your hand on his collar-bone*”. *This was evidently a pre-arranged sign to show that the Messenger was genuine. Abu Dawud transmitted it.
وَعَنْ جَابِرٍ قَالَ: أَرَدْتُ الْخُرُوجَ إِلَى خَيْبَرَ فَأَتَيْتُ النَّبِيَّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ فَسَلَّمْتُ عَلَيْهِ وَقُلْتُ: إِنِّي أَرَدْتُ الْخُرُوجَ إِلَى خَيْبَرَ فَقَالَ: «إِذَا أَتَيْتَ وَكِيلِي فَخُذْ مِنْهُ خَمْسَةَ عَشَرَ وَسْقًا فَإِنِ ابْتَغَى مِنْكَ آيَةً فَضَعْ يدك على ترقوته» . رَوَاهُ أَبُو دَاوُد
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