أَخْبَرَنَا مُحَمَّدُ بْنُ مَنْصُورٍ، قَالَ حَدَّثَنَا سُفْيَانُ، عَنْ عَاصِمِ بْنِ كُلَيْبٍ، عَنْ أَبِي بُرْدَةَ، قَالَ قَالَ عَلِيٌّ قَالَ لِي رَسُولُ اللَّهِ صلى الله عليه وسلم ‏"‏ يَا عَلِيُّ سَلِ اللَّهَ الْهُدَى وَالسَّدَادَ ‏"‏ ‏.‏ وَنَهَانِي أَنْ أَجْعَلَ الْخَاتَمَ فِي هَذِهِ وَهَذِهِ ‏.‏ وَأَشَارَ يَعْنِي بِالسَّبَّابَةِ وَالْوُسْطَى ‏.‏

It was narrated that Abu Burdah said: 'Ali said: "The Messenger of Allah [SAW] said to me: 'O 'Ali, ask Allah for guidance and steadfastness,' and he forbade me from placing a ring on this one and this one' - and he pointed to his forefinger and middle finger. Translation Not Available

Book Ref: Sunan An Nisai Book 48 Hadith 5210
Web Ref:  Sunan An Nisai Vol 6 Book 48 Hadith 5213