Usamah ibn Zayd narrates that the messenger of Allah, Allah send peace and blessings upon him said, he who is favoured by another, and he says to the one who favoured him
Allah reward you with good
Then certainly he has praised the one who favoured him well.
عن أسامة بن زيد رضي الله عنهما قال: قال رسول الله صلى الله عليه وسلم: من صنع إليه معروف، فقال لفاعله:
جَزَاكَ اللهُ خَيْرًا
فقد أبلغ في الثناء.
رواه الترمذي، كتاب الدعوات ،ح/ ١٤