Sahih al-Bukhari 7234Book 94, Hadith 9
حَدَّثَنَا مُحَمَّدٌ، حَدَّثَنَا عَبْدَةُ، عَنِ ابْنِ أَبِي خَالِدٍ، عَنْ قَيْسٍ، قَالَ أَتَيْنَا خَبَّابَ بْنَ الأَرَتِّ نَعُودُهُ وَقَدِ اكْتَوَى سَبْعًا فَقَالَ لَوْلاَ أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم نَهَانَا أَنْ نَدْعُوَ بِالْمَوْتِ لَدَعَوْتُ بِهِ.
We went to pay a visit to Khabbab bin Al-Art and he had got himself branded at seven spots over his body. He said, "If Allah's Messenger (ﷺ) had not forbidden us to invoke Allah for death, I would have invoked for it."