Al-Kāfi - Volume 4 > The Case of One Who Fasts on a Journey out of Ignorance
Hadith #1

1ـ عَلِيُّ بْنُ إِبْرَاهِيمَ عَنْ أَبِيهِ عَنِ ابْنِ أَبِي عُمَيْرٍ عَنْ حَمَّادٍ عَنِ الْحَلَبِيِّ عَنْ أَبِي عَبْدِ الله (عَلَيْهِ السَّلاَم) قَالَ قُلْتُ لَهُ رَجُلٌ صَامَ فِي السَّفَرِ فَقَالَ إِنْ كَانَ بَلَغَهُ أَنَّ رَسُولَ الله (صلَّى اللهُ عَلَيْهِ وَآلِه) نَهَى عَنْ ذَلِكَ فَعَلَيْهِ الْقَضَاءُ وَإِنْ لَمْ يَكُنْ بَلَغَهُ فَلا شَيْ‏ءَ عَلَيْهِ.

1. Ali ibn Ibrahim has narrated from his father from ibn abu ‘Umayr from Hammad from al-Halabiy who has said the following: “I once asked abu ‘ Abd Allah, ‘Alayhi al-Salam, about a man who fasts on journey. He (the Imam) said, ‘If he is informed that the Messenger of Allah, O Allah, grant compensation to Muhammad and his family worthy of their services to Your cause, prohibited fasting on a journey, he is required to complete its Qada’ (compensatory fast) but if such information has not reached him, he is not obligated for anything/”