The 9th year of the Hijrah is known as the ‘Year of the Delegations’ (سنة الوفود), in which each Arab tribe sent a group of representatives to meet with the Prophet ﷺ in Madinah. Apart from the Christians of Najran who chose to remain on their religion and pay the jizya, the rest of the Arab tribes accepted Islam and gave their bay’ah to the Prophet ﷺ. Since the bay’ah for many of these tribes and individuals was given at the same time as accepting Islam, this may lead someone to the conclusion that the bay’ah is related to belief, and withdrawing bay’ah is apostasy.
In response to this, bay’ah is related to ruling which is an action, and those who give bay’ah are already Muslim. The evidences for this are as follows.
1- Bay’ah is always taken from a believer
Allah (Most High) says:
يا أَيُّهَا النَّبِيُّ إِذا جاءَكَ المُؤمِناتُ يُبايِعنَكَ
“O Prophet! When women who have iman come to you pledging allegiance to you…”
لقد رضي الله عن المؤمنين إذ يبايعونك تحت الشجرة
“Allah was pleased with the believers when they pledged allegiance to you under the tree.”
إِنَّ الَّذينَ يُبايِعونَكَ إِنَّما يُبايِعونَ اللَّهَ
“Those who pledge you their allegiance pledge allegiance to Allah.”
When the Prophet ﷺ met members of the Al-Khazraj tribe at Hajj, two years before the hijra, six converted to Islam but there was no bay’ah. The following year ten members of Al-Khazraj and two from Al-Aws met with the Prophet ﷺ at Hajj and all were Muslim. When the Prophet ﷺ saw that their number had increased, and that they had started to convert members of their traditional enemy the Al-Aws tribe, he ﷺ saw a potential for gaining authority in Yathrib, so he ﷺ took the first bay’ah of Al-Aqaba from them, and then despatched Mus’ab ibn Umayr to prepare the society of Yathrib for Islam.
2- Bay’ah is not taken from a child whereas belief in Islam is accepted from a child
Zainab bint Humair took her son ‘Abdullah Ibn Hisham to the Messenger of Allah ﷺ and said: يَا رَسُولَ اللَّهِ بَايِعْهُ ‘O Messenger of Allah! Take his Bay’ah’. The Prophet ﷺ said: هُوَ صَغِيرٌ “He is young”, so he stroked his head and prayed for him.
Zubair ibn Al-Awwam asked his son Abdullah ibn Zubair to go to the Messenger of Allah ﷺ to give the bay’ah.
ثُمَّ جَاءَ وَهُوَ ابْنُ سَبْعِ سِنِينَ أَوْ ثَمَانٍ لِيُبَايِعَ رَسُولَ اللَّهِ صلى الله عليه وسلم وَأَمَرَهُ بِذَلِكَ الزُّبَيْرُ فَتَبَسَّمَ رَسُولُ اللَّهِ صلى الله عليه وسلم حِينَ رَآهُ مُقْبِلاً إِلَيْهِ ثُمَّ بَايَعَهُ
“He (Abdullah) went to him ﷺ when he had attained the age of seven or eight years in order to pledge allegiance to Allah’s Messenger ﷺ as Zubair had commanded him to do. Allah’s Messenger ﷺ smiled when he saw him coming towards him and then accepted his allegiance.”
Nawawi comments on this saying, هَذِهِ بَيْعَة تَبْرِيك وَتَشْرِيف لَا بَيْعَة تَكْلِيف “This is a bay’ah of blessing and honor, not a bay’ah of (shar’i) responsibility.”
This is different to accepting Islam, because reaching puberty is not a condition for becoming Muslim. We know from the seerah that Ali ibn Abi Talib was the first boy to accept Islam and he hadn’t reached puberty. Ibn Kathir says, “And the first boy to accept Islam was Ali ibn Abi Talib; he was young then and had not reached puberty – as generally believed.”
3- A Bedouin requested to be relieved of his bay’ah and wasn’t executed for apostasy
A Bedouin came to the Prophet ﷺ and said, بَايِعْنِي عَلَى الإِسْلاَمِ “Please take my bay’ah for Islam.” So the Prophet took from him the bay’ah for Islam. He came the next day with a fever and said to the Prophet ﷺ أَقِلْنِي “Cancel my pledge.” But the Prophet ﷺ refused and when the Bedouin went away, the Prophet said, الْمَدِينَةُ كَالْكِيرِ، تَنْفِي خَبَثَهَا، وَيَنْصَعُ طِيبُهَا “Madinah is like a pair of bellows (furnace): It expels its impurities and brightens and clears its good.”
Abdul-Qadeem Zaloom comments on this hadith, “It would be wrong to claim that the Bedouin wanted to leave Islam by seeking relief from his bay’ah rather than the obedience to the Head of State. This is because if this had been the case, his act would have been considered as apostasy, and the Messenger of Allah ﷺ would most certainly have killed him, since the punishment for the apostate is killing. The bay’ah itself is not a bay’ah for embracing Islam but for obedience. Therefore, the Bedouin wanted to rid himself from his oath of obedience, not to apostasise.”
So coming back to the original point that the tribes and individuals in Madinah gave bay’ah at the same time as accepting Islam, what actually happened was the bay’ah was combined, or made at the same time as the shahada to accept Islam. This is evident from Khalid bin Walid’s conversion to Islam, as narrated in the Seerah of Ibn Hisham where Khalid first accepted Islam (submitted) and then gave the bay’ah.
فَتَقَدَّمَ خَالِدُ بْنُ الْوَلِيدِ ، فَأَسْلَمَ وَبَايَعَ
“So Khalid bin Walid came forward and submitted, then gave bay’ah.”
 Holy Qur’an, Surah Al-Mumtahana, ayah 12
 Holy Qur’an, Surah Al-Fath, ayah 18
 Holy Qur’an, Surah Al-Fath, ayah 10
 Imam Nawawi, ‘Sharh Sahih Muslim,’ 14/126
 Ibn Kathir, ‘The Life of the Prophet Muhammad,’ translation of Al-Sira al-Nabawiyya,’ pp.314
 Abdul-Qadeem Zaloom, ‘The Ruling System in Islam,’ translation of Nizam ul-Hukm fil Islam, Khilafah Publications, Fifth Edition, p.125