Beyond actual transactions, trade serves here as an image: the most profitable sale is selling oneself to Allah, and the worst is exchanging guidance for error or Allah’s signs for a small price. These verses also present trade as the lawful alternative to usury and deal with taking witnesses in transactions and with forbidden purchases.
Verses gathered from a topical index of the Quran, in Mushaf order; every verse is quoted in full.
And believe in what I have sent down confirming that which is [already] with you, and be not the first to disbelieve in it. And do not exchange My signs for a small price, and fear [only] Me.
Indeed, We sent down the Torah, in which was guidance and light. The prophets who submitted [to Allāh] judged by it for the Jews, as did the rabbis and scholars by that with which they were entrusted of the Scripture of Allāh, and they were witnesses thereto. So do not fear the people but fear Me, and do not exchange My verses for a small price [i.e., worldly gain]. And whoever does not judge by what Allāh has revealed - then it is those who are the disbelievers.