[Machine] The Messenger of Allah ﷺ said, "Whoever is invited to the authority and does not respond, he is an oppressor with no right."  

قَالَ رَسُولُ اللهِ ﷺ «مَنْ دُعِيَ إِلَى سُلْطَانٍ فَلَمْ يُجِبْ فَهُوَ ظَالِمٌ لَا حَقَّ لَهُ»  

The Prophet ﷺ forbade selling animals for animals when payment was to be made at a later date. (Using translation from Abū Dāʾūd 3356)  

«أَنَّ النَّبِيَّ ﷺ نَهَى عَنْ بَيْعِ الْحَيَوَانِ بِالْحَيَوَانِ نَسِيئَةً»