It is narrated from Sayyiduna Ibn Umar (may Allah be pleased with them both) that the Messenger of Allah (peace and blessings be upon him) said: "Delay in payment by a wealthy person is injustice; when someone's debt is transferred to a wealthy person, he should accept it; and one should not make two sales in one sale."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الحوالة / 11390