It was narrated Abdullah bin Abi Rabi'ah (RA): The Prophet (ﷺ) borrowed forty thousand from me, when some wealth came to him, he then paid me back and said:

بَارَكَ اللَّهُ لَكَ فِي أَهْلِكَ وَمَالِكَ، إِنَّمَا جَزَاءُ السَّلَفِ الْحَمْدُ وَالْأَدَاءُ

BaarakAllahu laka fee 'ahlika wa maalika, 'innamaa jazaa'us-salafil-hamdu wal' adaa'u

May Allah bless you in your family and your wealth, surely the reward for a loan is praise and returning (what was borrowed).

Reference: Sahih. Nasa'i: 4683