Malik related to me from Ibn Shihab from Ibn Muhayyisa al-Ansari, one of the Banu Haritha, that he asked permission from the Messenger of Allah ﷺ to give payment for cupping, and he forbade him to do it. He continued to ask and seek his permission until he said, "Feed the ones who drive your water-carrying camels," meaning "your slaves."  

أَنَّهُ اسْتَأْذَنَ رَسُولَ اللَّهِ ﷺ فِي إِجَارَةِ الْحَجَّامِ فَنَهَاهُ عَنْهَا فَلَمْ يَزَلْ يَسْأَلُهُ وَيَسْتَأْذِنُهُ حَتَّى قَالَ اعْلِفْهُ نُضَّاحَكَ يَعْنِي رَقِيقَكَ  

Muhayyisah asked permission of the Messenger of Allah ﷺ regarding hire of the cupper, but he forbade him. He kept on asking his permission, and at last he said to him: Feed your watering camel with it and feed your slave with it. (Using translation from Abū Dāʾūd 3422)   

أَنَّهُ اسْتَأْذَنَ رَسُولَ اللهِ ﷺ فِي إِجَارَةِ الْحَجَّامِ فَنَهَاهُ عَنْهَا فَلَمْ يَزَلْ يَسْأَلْهُ فِيهَا حَتَّى قَالَ لَهُ اعْلِفْهُ نَاضِحَكَ وَأَطْعِمْهُ رَقِيقَكَ  

[Machine] He sought permission from the Messenger of Allah ﷺ regarding the harvest of the dates. If the Messenger of Allah ﷺ refused, he would continue to approach him and mention his need until he permitted him to harvest the ripe and tender dates.  

أَنَّهُ اسْتَأْذَنَ رَسُولَ اللهِ ﷺ فِي خَرَاجِ الْحَجَّامِ «فَمَنَعَهُ إِيَّاهُ فَلَمْ يَزَلْ يُرَاجِعُ رَسُولَ اللهِ ﷺ وَيُذْكُرُ لَهُ حَاجَتَهُ حَتَّى» أَذِنَ لَهُ أَنْ يَعْلِفَهَ نَاضِحَهُ وَرَقِيقَهُ