Al-Kāfi - Volume 4 > The Case of Those Who Need Permission to Fast Optional Fasting
Hadith #2

2ـ مُحَمَّدُ بْنُ يَحْيَى عَنْ مُحَمَّدِ بْنِ أَحْمَدَ عَنْ أَحْمَدَ بْنِ هِلالٍ عَنْ مَرْوَكِ بْنِ عُبَيْدٍ عَنْ نَشِيطِ بْنِ صَالِحٍ عَنْ هِشَامِ بْنِ الْحَكَمِ عَنْ أَبِي عَبْدِ الله (عَلَيْهِ السَّلاَم) قَالَ قَالَ رَسُولُ الله (صلَّى اللهُ عَلَيْهِ وَآلِه) مِنْ فِقْهِ الضَّيْفِ أَنْ لا يَصُومَ تَطَوُّعاً إِلاَّ بِإِذْنِ صَاحِبِهِ وَمِنْ طَاعَةِ الْمَرْأَةِ لِزَوْجِهَا أَنْ لا تَصُومَ تَطَوُّعاً إِلاَّ بِإِذْنِهِ وَأَمْرِهِ وَمِنْ صَلاحِ الْعَبْدِ وَطَاعَتِهِ وَنُصْحِهِ لِمَوْلاهُ أَنْ لا يَصُومَ تَطَوُّعاً إِلاَّ بِإِذْنِ مَوْلاهُ وَأَمْرِهِ وَمِنْ بِرِّ الْوَلَدِ أَنْ لا يَصُومَ تَطَوُّعاً إِلاَّ بِإِذْنِ أَبَوَيْهِ وَأَمْرِهِمَا وَإِلاَّ كَانَ الضَّيْفُ جَاهِلاً وَكَانَتِ الْمَرْأَةُ عَاصِيَةً وَكَانَ الْعَبْدُ فَاسِقاً عَاصِياً وَكَانَ الْوَلَدُ عَاقّاً.

2. Muhammad ibn Yahya has narrated from Muhammad ibn Ahmad from Ahmad ibn Hilal from Marwak ibn ‘Ubayd from Nashit ibn Salih from Hisham ibn al-Hakam who has said the following: “Abu ‘Abd Allah, ‘Alayhi al-Salam, has said that the Messenger of Allah, O Allah, grant compensation to Muhammad and his family worthy of their services to Your cause, has said, ‘A guest of good understanding does not fast an optional fast without permission from his host. An obedient wife does not fast an optional fast without permission and order from her husband. An obedient and disciplined slave does not fast an optional fast without permission and order by his master. Children with good and kind behavior do not fast an optional fast without permission and order from their parents; otherwise, a guest is ignorant, a woman disobedient, the slave a sinner and disobedient, and the child is an ignored one.”’