Talhah bin al-Nadr (may Allah have mercy on him) said: I heard Ibn Sirin (may Allah have mercy on him) say: They did not hold back fruits against debt. He said: Ibn Sirin (may Allah have mercy on him) said: But cash (gold and silver) should be held back against debt.
The Shaykh (may Allah have mercy on him) said: This is the old position of Imam al-Shafi'i (may Allah have mercy on him), in which he distinguished between manifest wealth and hidden wealth.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الزكاة / 7616