حَدَّثَنَا يَحْيَى بْنُ سَعِيدٍ عَنِ عُبَيْدِ اللَّهِ أَخْبَرَنِي نَافِعٌ عَنِ ابْنِ عُمَرَ كَانَ إِذَا جَدَّ بِهِ السَّيْرُ جَمَعَ بَيْنَ الْمَغْرِبِ وَالْعِشَاءِ بَعْدَمَا يَغِيبُ الشَّفَقُ وَيَقُولُ إِنَّ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ كَانَ إِذَا جَدَّ بِهِ السَّيْرُ جَمَعَ بَيْنَهُمَا
مسند امام احمد بن حنبل · Hadith 5163
It was narrated from Ibn 'Umar that if he wanted to hasten in travel, he would put Maghrib and 'lsha' together after the red afterglow disappeared, and he said: If the Messenger of Allah (PBUH) wanted to hasten in travel, he would put them together.
Translated by Dr. Muhammad Muhsin Khan · Reviewed by Islamic University of Madinah · Published March 2020