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كتاب الطلاق
68  
Divorce
(25)
Chapter: Al-Li'an
(25)
باب اللِّعَانِ
Sahih al-Bukhari 5301

Narrated Sahl bin Sa`d As-Sa`idi:

(a companion of Allah's Messenger (ﷺ)) Allah's Messenger (ﷺ), holding out his middle and index fingers, said, "My advent and the Hour's are like this (or like these)," namely, the period between his era and the Hour is like the distance between those two fingers, i.e., very short.

حَدَّثَنَا عَلِيُّ بْنُ عَبْدِ اللَّهِ، حَدَّثَنَا سُفْيَانُ، قَالَ أَبُو حَازِمٍ سَمِعْتُهُ مِنْ، سَهْلِ بْنِ سَعْدٍ السَّاعِدِيِّ صَاحِبِ رَسُولِ اللَّهِ صلى الله عليه وسلم يَقُولُ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم ‏ "‏ بُعِثْتُ أَنَا وَالسَّاعَةَ كَهَذِهِ مِنْ هَذِهِ أَوْ كَهَاتَيْنِ ‏"‏‏.‏ وَقَرَنَ بَيْنَ السَّبَّابَةِ وَالْوُسْطَى‏.‏
Reference : Sahih al-Bukhari 5301
In-book reference : Book 68, Hadith 50
USC-MSA web (English) reference : Vol. 7, Book 63, Hadith 221
  (deprecated numbering scheme)