I heard the Messenger of Allah ﷺ say: Allah the Exalted has said: I am Compassionate, and this has been derived from mercy. I have derived its name from My name. If anyone joins it, I shall join him, and if anyone cuts it off, I shall cut him off. (Using translation from Abū Dāʾūd 1694)

قَالَ رَسُولُ اللَّهِ ﷺ « قَالَ اللَّهُ تَبَارَكَ وَتَعَالَى أَنَا الرَّحْمَنُ خَلَقْتُ الرَّحِمَ وَشَقَقْتُ لَهَا اسْمًا مِنِ اسْمِي فَمَنْ وَصَلَهَا وَصَلْتُهُ وَمَنْ قَطَعَهَا بَتَتُّهُ»