Good Manners and Form (Al-Adab)
Ṣaḥīḥ al-Bukhārī 5988
إِنَّ الرَّحِمَ سُجْنَةٌ مِنَ الرَّحْمَنِ، فَقَالَ اللَّهُ مَنْ وَصَلَكِ وَصَلْتُهُ، وَمَنْ قَطَعَكِ قَطَعْتُهُ
inna ar-raḥima sujnatun mina ar-raḥmani, faqāla-Llāh man waṣalaki waṣaltuhu, waman qaṭaʿaki qaṭaʿtuhu
Transliteration generated from the Arabic vowel marks
The full narration
Narrated Abu Huraira:The Prophet (ﷺ) said, "The word 'Ar-Rahm (womb) derives its name from Ar-Rahman (i.e., one of the names of Allah) and Allah said: 'I will keep good relation with the one who will keep good relation with you, (womb i.e. Kith and Kin) and sever the relation with him who will sever the relation with you, (womb, i.e. Kith and Kin)
Source
Ṣaḥīḥ al-Bukhārī · 5988
Ṣaḥīḥ