Muwatta Malik, Book 54, Hadith 1799 (In-Book) ⓘ

Malik related to me that he heard that when the Messenger of Allah, may Allah bless him and grant him peace, set foot in the stirrup intending to travel, he would say, "In the name of Allah. O Allah! You are my companion in the journey and the Khalifa of my family. O Allah! Spread out the earth for us and make the journey easy for us. O Allah! I seek refuge with You from the hardship of the journey and from returning to sorrow and a distressing sight regarding property and family."

حَدَّثَنِي مَالِكٌ، أَنَّهُ بَلَغَهُ أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم كَانَ إِذَا وَضَعَ رِجْلَهُ فِي الْغَرْزِ وَهُوَ يُرِيدُ السَّفَرَ يَقُولُ ‏ "‏ بِاسْمِ اللَّهِ ‏.‏ اللَّهُمَّ أَنْتَ الصَّاحِبُ فِي السَّفَرِ وَالْخَلِيفَةُ فِي الأَهْلِ اللَّهُمَّ ازْوِ لَنَا الأَرْضَ وَهَوِّنْ عَلَيْنَا السَّفَرَ اللَّهُمَّ إِنِّي أَعُوذُ بِكَ مِنْ وَعْثَاءِ السَّفَرِ وَمِنْ كَآبَةِ الْمُنْقَلَبِ وَمِنْ سُوءِ الْمَنْظَرِ فِي الْمَالِ وَالأَهْلِ ‏" ‏ ‏.‏