Jami at-Tirmidhi 1673
Jami at-Tirmidhi · Book 23: The Book on Jihad · What Has Been Related About It Being Disliked For A Man To Travel Alone
Narrated Ibn 'Umar:
حَدَّثَنَا أَحْمَدُ بْنُ عَبْدَةَ الضَّبِّيُّ الْبَصْرِيُّ ، حَدَّثَنَا سُفْيَانُ بْنُ عُيَيْنَةَ ، عَنْ عَاصِمِ بْنِ مُحَمَّدٍ ، عَنْ أَبِيهِ ، عَنِ ابْنِ عُمَرَ ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ " لَوْ أَنَّ النَّاسَ يَعْلَمُونَ مَا أَعْلَمُ مِنَ الْوَحْدَةِ مَا سَرَى رَاكِبٌ بِلَيْلٍ " . يَعْنِي وَحْدَهُ .
That the Messenger of Allah (ﷺ) said: "If the people knew what I know about being alone, then a rider would not journey at night." - meaning alone.
Grade: Sahih (Darussalam)