Iranian cleric Ayatollah Mohammad Hadi Yousefi Gharavi has stated the call to Islamic brotherhood and faith along with its requirements is a heavenly, divine and Quranic call.

 The speech comes as follows:
In the Name of God, the Compassionate, the Merciful
Praise be to God. Greetings to our Prophet, Muhammad (PBUH) and his infallible household. I also salute you dear brothers and sisters attending the conference.
In the beginning of my speech, I should say that a person believing in God, Prophet and his book, should follow whatever is in the book. God has at least in two verses invited Muslims to Islamic brothers in faith. The following verse testifies this: Verily, the faithful are brothers to each other. Yes... Muslims are brothers. However, there are certain people in Islamic Ummah, who do not pay attention to this. Unfortunately, certain people in Islamic Ummah does not make the least efforts to follow the divine call.
This is while adherence to the Islamic brotherhood and faith by believers and Muslims means serving God Almighty. Unfortunately, we see that some people claim to be servants of God Almighty and claim to follow the Messenger of God (PBUH) and the book revealed to him, but in practice they do not follow the divine instructions regarding the Islamic brotherhood.
Therefore, the call to Islamic brotherhood and faith along with its requirements is a heavenly, divine and Quranic call. This is a call that was revealed to the Prophet (PBUH). The Holy Prophet (PBUH) moved in the same way and holy Imams (peace be upon them) also walked in the same way after him. By pure Imams (peace be upon them), we mean Commander of the Faithful and his innocent children, including Imam Hassan (Peace Be Upon Him) and Imam Hussain (Peace Be Upon Him); The children who are actually the descendants of the Holy Prophet (PBUH). Didn't the infallible household of Holy Prophet (peace be upon them) follow the same policy after the Holy Prophet (PBUH)? Like the Holy Prophet (PBUH), they invited Muslims to the brotherhood in faith. Even to this day, when God's last legatee is in absentia, this invitation has never been rejected. Just as the Holy Prophet (PBUH) was the last messenger of God, Hazrat Hojjat bin Al-Hassan Al-Mahdi (AJ) is also the last legatee of God on earth.
The infallible household of Holy Prophet (peace be upon them) all took steps in the direction of what God revealed to His Prophet and invited Muslims to brotherhood. We also saw this invitation in the words of the Holy Prophet (PBUH); Where he said: "The example of the believers in their unity, compassion, and passion, is the example of the body, if a member complains of it, it complains to the rest of the body in the morning and the fever" (Believers are one body in friendship, affection and compassion towards each other, and when any part of it hurts, insomnia and fever cover other members. Is it really not? Brotherhood is the requisite of faith in God, the Prophet of God (PBUH) and the Book of God. We also find verses in line with the tradition of the Holy Prophet (PBUH), in the works of the famous Persian-speaking poet, Saadi Shirazi, who says: "The children of Adam are members of each other who are a gem in creation."
Of course, the late professor Shahid Motahari raised a consideration regarding this verse from the poems of Saadi Shirazi and said: "The Messenger of God said that the believers, and not the sons of Adam, are like a single body in friendship, compassion and kindness." Anyway, what seems clear is that the great Persian-language poet has widened the circle of faith and Islamic brotherhood and expanded it to human brotherhood. Here I must mention the famous letter of Commander of the Faithful (Peace Be Upon Him) to Malik Ashtar. When Malik Ashtar was appointed to govern Egypt, this letter was addressed to him by Imam Ali (Peace Be Upon Him). Of course, Malik never took over the government of Egypt, because he was poisoned and martyred by poison mixed with honey. After that, the perpetrators of this act rejoiced and said: "God has an army of honey!"
The words of Commander of the Faithful (Peace Be Upon Him) were collected by the late Sayyid Sharif Razi, one of his descendants, and presented in the book, entitled Nahj al-Balagheh. Abbas Mahmoud al-Akkad, a famous Egyptian writer, has cited Nahj al-Balaghah in his book titled "Genius of Amir al-Mu'minin" (PBUH). This famous Egyptian author states about this book: "Even if we assume that the words written in Nahj al-Balagha are not directly from the statements of the Commander of the Faithful (Peace Be Upon Him), it should be said that these words were written by one of his descendants named Sayyid Sharif Radi. He has entered the field of writing and he has not deviated from the truth as much as a needle's head in describing the statements of Commander of the Faithful) (Peace Be Upon Him) and his thoughts. This is the exact description that Al-Akkad gave in relation to Nahj al-Balagheh in order to validate the correctness of attributing the contents of the book to Commander of the Faithful (Peace Be Upon Him).
It is stated in Nahj al-Balagha that Hazrat Ali (Peace Be Upon Him) wrote his letter addressed to Malik Ashtar; Otherwise, today it was said that the letter was addressed to Muhammad bin Abu Bakr, the ruler of Egypt. At that time, when the letter fell into the hands of Muawiyah bin Abu Sufyan, it was rumored that the letter was addressed to Muhammad bin Abu Bakr, the ruler of Egypt. This is while the letter was originally addressed to Malek Ashtar Nakhai. Imam Ali (Peace Be Upon Him) emphasized in this letter:
 
“People are of two types; Either a brother to you in religion, or an equal to you in creation.”
Based on this statement of Hazrat Ali (Peace Be Upon Him), we believe that we should expand the circle of Islamic brotherhood and faith and expand it to brotherhood between humans and humanity. The reason is that Commander of the Faithful (Peace Be Upon Him) was the spokesman of Islam [Islamic rules]. Therefore, no one can doubt in this tradition from Hazrat Ali (Peace Be Upon Him) who said: "People are of two groups, either they are brothers with you in religion or they are equal with you in creation [that is, humanity].
Now, if the logic of Commander of the Faithful (Peace Be Upon Him) and his thinking were like this, then how should our logic be towards the brotherhood of faith? What should be the logic of those who claim to be Shiites and followers of Commander of the Faithful (Peace Be Upon Him)? What should be the logic of those who claim to be followers of the infallible household of Holy Prophet (peace be upon them)? Can any of the followers and Shias of the infallible household of Holy Prophet (peace be upon them) claim that they [the infallible household of Holy Prophet] deviated a bit from this path [calling for the brotherhood of faith, Islam and man]? When we say the infallible household of Holy Prophet (peace be upon them), we mean Hazrat Ali (PBUH), Hasan bin Ali (PBUH), Hussein bin Ali (PBUH), Ali bin Al-Hussein Zain al-Abidin (PBUH), Muhammad bin Ali al-Baqir (PBUH), Jafar bin Muhammad Al-Sadiq (PBUH), Musa bin Jafar (PBUH), Ali bin Musa al-Reza (PBUH), Muhammad bin Ali al-Jawad (PBUH), Ali bin Muhammad al-Hadi (PBUH), Hassan bin Ali bin Muhammad al-Askari (PBUH) and Hazrat Hojjat (PBUH). Can anyone claim that the infallible household of Holy Prophet (peace be upon them) distanced a bit from the call to brotherhood of faith and humanity? Definitely not... I swear to God Almighty that they not only called for the brotherhood of faith and Islam, but beyond that, they called all humans and all humanity to unity and integrity, let alone faith and Islam unity.