5-39 (The compiler of the book narrated) that his father - may God be pleased with him - narrated that Sa’ed ibn Abdullah quoted Ibrahim ibn Hashim, on the authority of Al-Nawfaly, on the authority of Al-Sakoony, on the authority of Aba Abdullah as-Sadiq (MGB), on the authority of his father (MGB), on the authority of his forefathers (MGB), on the authority of Ali (MGB) that God’s Prophet (MGB) said,

“Whoever engages in buying and selling should avoid the following five things. He should not do any business if he cannot do so. They are as follows: usury; swearing to something or someone; covering up the defects of his goods; praising the goods while selling them, and finding faults with goods while buying them.”