the Prophet (ﷺ) bought Safiyyah for seven slaves. (Sahih) (One of the narrators) 'Abdur-Rahman said: "From Dihyah Kalbi.'
Sunan Ibn Majah Book 12, Hadith 136
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Sunan Ibn Majah Book 12, Hadith 135 Next Hadith → ' "'On the night in which I was taken on the Night Journey (Al-Isra'), I came to people whose stomachs were like houses, in which there were snakes that could be seen from outside their stomachs. I said: 'Who are these, O Jibra’il?’ He said: 'They are the ones who consumed usury."'

Sunan Ibn Majah Book 12, Hadith 137