Amir al-Muminin (peace be upon him), as one who embodied complete submission to God and sincere struggle in his life, was a manifestation of acting upon the content of verses 111 and 112 of Surah at-Tawbah.
Verse 111 of Surah at-Tawbah
إِنَّ اللهَ اشْتَرى مِنَ الْمُؤْمِنينَ أَنْفُسَهُمْ وَ أَمْوالَهُمْ بِأَنَّ لَهُمُ الْجَنَّةَ، يُقاتِلُونَ في سَبيلِ اللهِ فَيَقْتُلُونَ وَ يُقْتَلُونَ، وَعْداً عَلَيْهِ حَقًّا فِي التَّوْراةِ وَ الْإِنْجيلِ وَ الْقُرْآنِ، وَ مَنْ أَوْفى بِعَهْدِهِ مِنَ اللهِ، فَاسْتَبْشِرُوا بِبَيْعِكُمُ الَّذي بايَعْتُمْ بِهِ، وَ ذلِكَ هُوَ الْفَوْزُ الْعَظيمُ
Indeed, Allah has purchased from the believers their lives and their properties [in exchange] that they will have Paradise. They fight in the cause of Allah, so they kill and are killed. [It is] a true promise [binding] upon Him in the Torah and the Gospel and the Quran. And who is more faithful to his covenant than Allah? So rejoice in your transaction which you have contracted. And it is that which is the great attainment.
Verse 112 of Surah at-Tawbah
التَّائِبُونَ الْعابِدُونَ الْحامِدُونَ السَّائِحُونَ الرَّاكِعُونَ السَّاجِدُونَ الْآمِرُونَ بِالْمَعْرُوفِ وَ النَّاهُونَ عَنِ الْمُنْكَرِ وَ الْحافِظُونَ لِحُدُودِ اللهِ، وَ بَشِّرِ الْمُؤْمِنينَ
[They are] those who repent, those who worship, those who praise [Him], those who fast, those who bow, those who prostrate, those who enjoin what is right and forbid what is wrong, and those who observe the limits of Allah. And give good tidings to the believers.
According to a narration from Imam al-Hadi (peace be upon him) in the Al-Ghadir Pilgrimage prayer, these verses recall the exalted station of Amir al-Muminin (peace be upon him).
In a passage of the Al-Ghadir Pilgrimage prayer, referring to verse 111 of Surah at-Tawbah, it is stated:
أَشْهَدُ أَنَّكَ وَعَمَّكَ وَأَخَاكَ أَصْحَابُ الْبَيْعَةِ لِلَّهِ الَّذِينَ بَايَعُوا اللَّهَ بِأَنْفُسِهِمْ، فَأَنْزَلَ اللَّهُ فِيكُمْ: إِنَّ اللَّهَ اشْتَرَى مِنَ الْمُؤْمِنِينَ أَنْفُسَهُمْ وَأَمْوَالَهُمْ بِأَنَّ لَهُمُ الْجَنَّةَ...
“I bear witness that you, your uncle, and your brother are those who conducted a transaction with Allah through your souls. Then Allah revealed this verse concerning you: ‘Indeed, Allah has purchased from the believers their lives and their properties [in exchange] that they will have Paradise…'”
In another passage of the Al-Ghadir Pilgrimage prayer, referring to verse 112 of Surah at-Tawbah, it is stated:
أَشْهَدُ أَنَّكَ وَعَمَّكَ وَأَخَاكَ أَصْحَابُ الْبَيْعَةِ لِلَّهِ الَّذِينَ بَايَعُوا اللَّهَ بِأَنْفُسِهِمْ، فَأَنْزَلَ اللَّهُ فِيكُمْ: التَّائِبُونَ الْعَابِدُونَ الْحَامِدُونَ السَّائِحُونَ...»
“I bear witness that you, your uncle, and your brother are those who conducted a transaction with Allah through your souls. Then Allah revealed this verse concerning you: ‘Those who repent, those who worship, those who praise [Him], those who fast…'”
Amir al-Muminin (peace be upon him) is an example of the believers described in verses 111 and 112 of Surah at-Tawbah, which are considered ‘Alawi verses in the Noble Quran. In some narrations, it is mentioned that Amir al-Muminin (peace be upon him), on the night of Laylat al-Mabit, when he slept in the bed of the Final Prophet (peace be upon him and his family) to protect the life of the Messenger of God, was a complete manifestation of this type of divine transaction, for he offered his life without any blemish.
Imam Hasan al-Askari (peace be upon him) narrated in a tradition, citing his noble father, Imam al-Hadi (peace be upon him), that on the day of Eid, he (Imam al-Hadi) went to visit the shrine of Amir al-Muminin (peace be upon him) and said:
أَشْهَدُ أَنَّكَ أَمِيرَ الْمُؤْمِنِينَ (عَلَيْهِ السَّلَامُ)؛ هُوَ الْحَقُّ الَّذِي نَطَقَ الْقُرْآنُ بِوَلَايَتِكَ، وَأَخَذَ لَكَ رَسُولُ اللَّهِ الْعَهْدَ عَلَى الْأُمَّةِ. وَأَشْهَدُ أَنَّكَ وَعَمَّكَ وَأَخَاكَ أَصْحَابُ الْبَيْعَةِ لِلَّهِ الَّذِينَ بَايَعُوا اللَّهَ بِأَنْفُسِهِمْ، فَأَنْزَلَ اللَّهُ فِيكُمْ: إِنَّ اللَّهَ اشْتَرَى مِنَ الْمُؤْمِنِينَ أَنْفُسَهُمْ وَأَمْوَالَهُمْ بِأَنَّ لَهُمُ الْجَنَّةَ... (إِلَى قَوْلِهِ) وَبَشِّرِ الْمُؤْمِنِينَ
“I bear witness that you are Amir al-Muminin (peace be upon him)—the very truth concerning which the Quran spoke regarding your guardianship (Wilayah), and for which the Messenger of Allah took a covenant from the Ummah on your behalf. And I bear witness that you, your uncle, and your brother are those who conducted a transaction with Allah through their souls. Then Allah revealed concerning you: ‘Indeed, Allah has purchased from the believers their lives and their properties [in exchange] that they will have Paradise… (to His words) …and give good tidings to the believers.'”
Tafsir Ahl al-Bayt (peace be upon them), vol. 6, p. 346; Bihar al-Anwar, vol. 97, p. 359
