Anas reported: The Prophet, peace and blessings be upon him, said, “Verily, the womb has an iron hook attached firmly to the Throne, speaking with a penetrating tongue: O Allah, keep relations with whoever keeps relations with me, and sever relations with whoever severs them with me. Allah Almighty says: I am the Gracious, the Merciful. I derived the womb from My name. Whoever keeps relations with it, I keep relations with him. Whoever cuts off relations with it, I cut off relations with him.”
Source: Musnad al-Bazzār 6495
Grade: Hasan li ghayrihi (fair due to external evidence) according to Al-Albani
عن أنسٍ عَنِ النَّبِيِّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ أَنَّهُ قَالَ إِنَّ لِلرَّحِمِ حُجْنَةً مُتَمَسِّكَةً بِالْعَرْشِ تَكَّلَّمُ بِلِسَانٍ ذَلِقٍ اللَّهُمَّ صِلْ مَنْ وَصَلَنِي وَاقْطَعْ مَنْ قَطَعَنِي فَيَقُولُ اللَّهُ تَبَارَكَ وَتَعَالَى أَنَا الرَّحْمَنُ الرَّحِيمُ وَإِنِّي شَقَقْتُ الرَّحِمَ مِنَ اسْمِي فَمَنْ وَصَلَهَا وَصَلْتُهُ وَمَنْ بَتَكَهَا بَتَكْتُهُ
6495 مسند البزار
2531 المحدث الألباني خلاصة حكم المحدث حسن لغيره في صحيح الترغيب