What is the ruling when a seller agrees to sell an item on condition that the buyer mortgages two specific slaves for the price, but the buyer claims the condition was only to mortgage one slave?

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There are two established rulings regarding this dispute over the terms of the mortgage condition in a sale. The first opinion holds that both parties must swear mutual oaths (تحالفان), as the disagreement concerns the sale agreement itself, equivalent to a dispute over the price. The second, stronger opinion maintains that the statement of the mortgagor (the buyer) is accepted, as he is denying the condition of mortgaging the specified slave, and the denial takes precedence.