The Messenger of Allah ﷺ said, "A wealthy person's delay in repaying a debt is an injustice."
حدثنا عبد الأعلى عن معمر عن همام بن منبه أخي وهب أنه
قال رسول الله ﷺ مطل الغني ظلم
No references are available.
Its isnad is sahih. Bukhari related it (46:5) from Musaddad, from Abdul-Ala, with this same isnad. Muslim also related it (1:460) with a similar meaning, but without giving its exact wording, through the narration of Isa bin Yunus and Abdul-Razzaq, both from Maamar. Its meaning has already passed at greater length with a similar wording (7332, 7446).