يعتبر فيه قبض عوضيه في المجلس
Translation: Possession of both countervalues during the contracting session is required.
Quduri requires possession of both countervalues in sarf. Where gold is exchanged for silver, the legally effective receipt of each must occur within the contracting session.
If one countervalue is delivered now and the other merely promised for tomorrow, the sarf possession condition fails. Equality is a separate question: gold and silver are different genera, allowing different quantities, but the session-possession requirement remains.