عن أبي هريرة رضي الله عنه أن رسول الله صلى الله عليه وسلم قال: «مَطْلُ الغني ظلم، وإذا أُتْبِعَ أحدكم على مَلِيءٍ فَلْيَتْبَعْ». [صحيح] - [متفق عليه] المزيــد ...
Abu Hurayrah (may Allah be pleased with him) reported that the Messenger of Allah (may Allah's peace and blessings be upon him) said: "Procrastination in payment of a debt by a rich man is injustice, but when one of you is referred for payment to a wealthy man, let him be referred." Sahih/Authentic. - [Al-Bukhari and Muslim]
This Hadīth guides to one of the manners of kind treatment.
In this Hadīth, the Prophet (may Allah's peace and blessings be upon him) orders the debtor to pay the debt kindly and advises the creditor to request what is his kindly as well.
The Prophet (may Allah's peace and blessings be upon him) clarified that if the creditor demanded his money, or his demand was understood from a sign or a hint, then delaying his right on the part of the wealthy debtor - who can afford to pay his debt - would be considered injustice because the debtor, in this case, would be holding back the creditor's right without an excuse.
Such injustice would be alleviated in case the debtor transfers his creditor to another debtor who can pay him the debt easily. At that point, the creditor is advised to accept that transfer. The acceptance would be an expression of polite demand of the debt as well as an easier means to take his money; not to mention that injustice, which would have continued had the debt remained in the procrastinator's liability, would be alleviated.