بُلُوغُ الْمَرَامِ
Bulugh al-Maram 441
The Book of Prayer
وَعَنْ جَابِرٍ - رضى الله عنه - قَالَ: قَالَ رَسُولُ اَللَّهِ - صلى الله عليه وسلم -{ خَيْرُ أُمَّتِي اَلَّذِينَ إِذَا أَسَاءُوا اِسْتَغْفَرُوا, وَإِذَا سَافَرُوا قَصَرُوا وَأَفْطَرُوا } أَخْرَجَهُ اَلطَّبَرَانِيُّ فِي اَلْأَوْسَطِ بِإِسْنَادٍ ضَعِيفٍ . [1] .
Narrated Jabir (RA): Allah's Messenger (ﷺ) said: "The best of my followers are those who, having done evil, ask for forgiveness (from Allah); and when on a journey, shorten (the prayer) and break the fast." [at-Tabarani reported it in al-'Awsat through a weak chain of narrators].
Sunnah.com reference: Book 2, Hadith 355