A vow is an act of worship, and therefore, it must be for God alone; as He has said: ﴿فَمَنْ كَانَ يَرْجُو لِقَاءَ رَبِّهِ فَلْيَعْمَلْ عَمَلًا صَالِحًا وَلَا يُشْرِكْ بِعِبَادَةِ رَبِّهِ أَحَدًا﴾[1]; “So whoever hopes to meet his Lord, he shall do righteous deeds and not associate anyone in the worship of his Lord,” and said in the words of the wife of Imran: ﴿رَبِّ إِنِّي نَذَرْتُ لَكَ مَا فِي بَطْنِي مُحَرَّرًا فَتَقَبَّلْ مِنِّي ۖ إِنَّكَ أَنْتَ السَّمِيعُ الْعَلِيمُ﴾[2]; “O Lord! I vowed to dedicate to You what is in my womb, so accept it from me. You are indeed the All-Hearing, the All-Knowing.” So if you have intended to make a vow for God and the Ahl al-Bayt together, then your vow is invalid; similarly, if you intend to perform prayer and fast for God and the Ahl al-Bayt together, your prayer and fast are invalid, and the evidence for that is His words: ﴿لَئِنْ أَشْرَكْتَ لَيَحْبَطَنَّ عَمَلُكَ وَلَتَكُونَنَّ مِنَ الْخَاسِرِينَ﴾[3]; “If you associate (others with God), your deed will come to nothing, and you will be one of the losers,” and the fact that the Ahl al-Bayt are God’s friends and intercessors on the Day of Judgment is clearly not evidence of the permissibility of worshiping them with God; as He has said: ﴿أَلَا لِلَّهِ الدِّينُ الْخَالِصُ ۚ وَالَّذِينَ اتَّخَذُوا مِنْ دُونِهِ أَوْلِيَاءَ مَا نَعْبُدُهُمْ إِلَّا لِيُقَرِّبُونَا إِلَى اللَّهِ زُلْفَى إِنَّ اللَّهَ يَحْكُمُ بَيْنَهُمْ فِي مَا هُمْ فِيهِ يَخْتَلِفُونَ ۗ إِنَّ اللَّهَ لَا يَهْدِي مَنْ هُوَ كَاذِبٌ كَفَّارٌ﴾[4]; “Be aware that the pure religion is for God. Those who took guardians other than him (say), ‘We do not worship them except that they may bring us closer to God.’ Indeed, God will judge among them concerning what they disagree about. Surely, God does not guide one who is an ungrateful liar,” and said: ﴿وَيَعْبُدُونَ مِنْ دُونِ اللَّهِ مَا لَا يَضُرُّهُمْ وَلَا يَنْفَعُهُمْ وَيَقُولُونَ هَؤُلَاءِ شُفَعَاؤُنَا عِنْدَ اللَّهِ ۚ قُلْ أَتُنَبِّئُونَ اللَّهَ بِمَا لَا يَعْلَمُ فِي السَّمَاوَاتِ وَلَا فِي الْأَرْضِ ۚ سُبْحَانَهُ وَتَعَالَى عَمَّا يُشْرِكُونَ﴾[5]; “And besides God, they worship those who do not benefit or harm them, and they say: ‘These are our intercessors before God.’ Say: ‘Do you inform God of what He does not know about in the heavens or on the earth?’ Glorified and Exalted is He above what they associate (with Him)” and said: ﴿اتَّخَذُوا أَحْبَارَهُمْ وَرُهْبَانَهُمْ أَرْبَابًا مِنْ دُونِ اللَّهِ وَالْمَسِيحَ ابْنَ مَرْيَمَ وَمَا أُمِرُوا إِلَّا لِيَعْبُدُوا إِلَهًا وَاحِدًا ۖ لَا إِلَهَ إِلَّا هُوَ ۚ سُبْحَانَهُ عَمَّا يُشْرِكُونَ﴾[6]; “They took their scholars and monks as well as the Messiah, son of Maryam, as gods other than God, whereas they were not commanded but to worship One God. There is no god but He! Glorified is He above what they associate (with Him),” and said: ﴿وَلَا يَأْمُرَكُمْ أَنْ تَتَّخِذُوا الْمَلَائِكَةَ وَالنَّبِيِّينَ أَرْبَابًا ۗ أَيَأْمُرُكُمْ بِالْكُفْرِ بَعْدَ إِذْ أَنْتُمْ مُسْلِمُونَ﴾[7]; “And He does not command you to take the Angels and the Prophets as gods. Does He command you to disbelief after you are Muslims?!” All of these verses explicitly indicate that it is not permissible to associate the Prophets and the righteous in the worship of God, so one who associates them in it while claiming to be their follower has contradicted himself; because he does that which they would forbid, while the Shias of a person are those who follow him; as it has been narrated from Abu Ja‘far Muhammad ibn Ali, peace be upon them, that he said: «إِنَّمَا شِيعَتُنَا مَنْ تَابَعَنَا وَلَمْ يُخَالِفْنَا»[8]; “Our Shia is the one who follows us and does not oppose us,” and from Ja‘far ibn Muhammad al-Sadiq, peace be upon them: that he said: «لَيْسَ مِنْ شِيعَتِنَا مَنْ قَالَ بِلِسَانِهِ وَخَالَفَنَا فِي أَعْمَالِنَا وَآثَارِنَا، وَلَكِنْ شِيعَتُنَا مَنْ وَافَقَنَا بِلِسَانِهِ وَقَلْبِهِ وَاتَّبَعَ آثَارَنَا وَعَمِلَ بِأَعْمَالِنَا، أُولِئَكَ مِنْ شِيعَتِنَا»[9]; “One who agrees (with us) in his words but opposes us in our deeds and manners is not from our Shias, but rather our Shia is one who agrees with us with his tongue and heart, follows our way, and acts on our deeds. They are our true Shias.”

If the vow is invalid, it is not obligatory to fulfill it, nor is there any expiation for it, and it is only obligatory to ask God for forgiveness for it; because it is a bad deed, but if God Almighty has fulfilled the need for which you made an invalid vow, it is recommended that you perform the act of worship that you vowed to do with the intention of gratitude, not with the intention of fulfillment or expiation, and if He has not fulfilled your need yet, then you can repeat your vow correctly if you wish, and making dua a lot is better than making a vow; as it has been narrated from the Messenger of God, peace and blessings of God be upon him and his family, that he said: «إِنَّ النَّذْرَ لَا يُقَدِّمُ شَيْئًا، وَإِنَّمَا يُسْتَخْرَجُ بِهِ مِنَ الْبَخِيلِ»[1]; “The vow does not hasten anything, and it is only a means by which (something) is extracted from the miserly person,” and it has been said in a narration from him and his Ahl al-Bayt: «أَفْضَلُ الْعِبَادَةِ الدُّعَاءُ»[2]; “The best act of worship is dua.”