عَنِ ابْنِ عُمَرَ أَنَّ النَّبِيَّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ قَالَ: " أَرَانِي فِي الْمَنَامِ أَتَسَوَّكُ بِسِوَاكٍ فَجَاءَنِي رَجُلَانِ أَحَدُهُمَا أَكْبَرُ مِنَ الْآخَرِ فَنَاوَلْتُ السِّوَاكَ الْأَصْغَرَ مِنْهُمَا فَقِيلَ لي: كبر فَدَفَعته إِلَى الْأَكْبَر مِنْهُمَا "

Ibn ‘Umar reported the Prophet as saying, “I had a dream in which I was using a tooth-stick, when two men, one older than the other, came to me. I handed the tooth-stick to the younger of the two and was told to respect the senior, so I handed it to the older.” (Bukhari and Muslim.)