Can a mukatab (a contracted slave) engage in buying and selling?

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The mukatab is permitted to buy and sell by scholarly consensus. This is because the contract of kitabah (manumission contract) is for the purpose of achieving freedom, which requires fulfilling its compensation. Fulfillment is only possible through acquisition, and trade is considered one of the strongest means of acquisition. Evidence suggests that nine-tenths of sustenance is found in trade, as mentioned in some narrations. He may accept and give in matters that benefit his wealth and aid in its accumulation.