TIRMIDHI 1260:
from ʿAmr b. Shuʿayb from his father from his grandfather —
From his father, from his grandfather that he heard the Messenger of Allah ﷺ delivering a Khutbah in which he said: "Whoever gives a writ of emancipation to his slave, for one hundred Uqiyyah, and he pays it to him less then ten Uqiyah." - or he said: "Ten Dirham" - "then he becomes incapable (of paying the remainder), the he remains a slave."
الترمذي ١٢٦٠:
عن عمرو بن شعيب عن أبيه عن جده —
سَمِعْتُ رَسُولَ اللَّهِ ﷺ يَخْطُبُ يَقُولُ مَنْ كَاتَبَ عَبْدَهُ عَلَى مِائَةِ أُوقِيَّةٍ فَأَدَّاهَا إِلاَّ عَشْرَ أَوَاقٍ أَوْ قَالَ عَشَرَةَ دَرَاهِمَ ثُمَّ عَجَزَ فَهُوَ رَقِيقٌ
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