Commentary:
It appears that when a member of the caravan took Joseph out of the well, his brethren became apprised of it and, declaring Joseph to be their slave, sold him to that very caravan for a paltry price. Thus the pronoun "they" in the clause, they sold him for a paltry price, stands for Joseph’s brethren and not for the caravan. The pronoun in the expression (of it) may mean either "him" or "it," standing either for Joseph or the price.
The Bible tells us that Joseph’s brothers sold him for twenty pieces of silver (Gen. 37:28). Their object in selling Joseph was obviously not to get money; they only did so fearing that if they did not declare Joseph to be their slave, the caravan might take him to be a free man and might send him home. So they represented him as their slave, and sold him for a small sum.
The context of the Quran also shows that those who are spoken of in this verse as selling Joseph were his brothers, and not the people of the caravan. For, in the preceding verse it has been said that when the caravan found Joseph, "they concealed him as a piece of good merchandise," whereas, in the verse under comment, we read that those who sold Joseph displayed no interest in him and "were not desirous" either of Joseph or of the price. This shows that those who are here spoken of as selling Joseph were not the members of the caravan, but, as the Bible tells us, Joseph’s own brethren.
The verse refers to another difference between the Bible and the Quran. According to the Bible, it was not a member of the caravan who drew Joseph from the well but Joseph’s own brothers (Gen. 37:28). The unreliability of the Biblical version is apparent from the fact that the passage dealing with this incident is full of contradictions. The Talmud also contradicts the Biblical account, and its description of this incident agrees with that of the Quran (Jew. Enc. under Joseph).