The love between the first caliph, Sayyiduna Abu Bakr Siddiqueرَضِىَ الـلّٰـهُ عَـنْهُand the fourth caliph, Sayyiduna Ali al-Murtadaرَضِىَ الـلّٰـهُ عَـنْهُwas unique. These two individuals had established a deep relationship of love and brotherhood, the extent of which can be seen through the sayings of Sayyiduna Ali al-Murtadaرَضِىَ الـلّٰـهُ عَـنْهُ, for on several occasions, he expressed the rank of Sayyiduna Siddiq al-Akbarرَضِىَ الـلّٰـهُ عَـنْهُ. Sayyiduna Aliرَضِىَ الـلّٰـهُ عَـنْهُstated regarding the bravery of Sayyiduna Abu Bakr Siddiqueرَضِىَ الـلّٰـهُ عَـنْهُ: ‘On the day of Badr, we built a canopy for the protection and service of the Prophetصَلَّى اللهُ عَلَيْهِ وَاٰلِهٖ وَسَلَّم. None of us advanced forward except Abu Bakr Siddiqueرَضِىَ الـلّٰـهُ عَـنْهُwho stood by the Prophetصَلَّى اللهُ عَلَيْهِ وَاٰلِهٖ وَسَلَّمwith a naked sword. No disbeliever came close to the Prophetصَلَّى اللهُ عَلَيْهِ وَاٰلِهٖ وَسَلَّمand this is why, from amongst us, the bravest is Sayyiduna Abu Bakr Siddiqueرَضِىَ الـلّٰـهُ عَـنْهُ.’ [Kanz ul ‘Umaal, Vol. 6, p. 235. Hadith. 35685]
On one occasion, he stated regarding the passion of faith of Sayyiduna Abu Bakr Siddiqueرَضِىَ الـلّٰـهُ عَـنْهُ: ‘I swear by Allah, one moment from the blessed life of Sayyiduna Abu Bakr Siddiqueرَضِىَ الـلّٰـهُ عَـنْهُ is better than thousands of moments from the life of the believer from the family of Fir’awn. That person (the believer from the family of Fir’awn) would hide his faith and this pure being would publicly announce his faith.’ [Masnad Al-Bazaar, Vol. 3, p. 15. Hadith. 761]
Maula Aliکرم اللہ تعالی وجہہ الکریمwould consider Sayyiduna Abu Bakr Siddiqueرَضِىَ الـلّٰـهُ عَـنْهُsuperior in matters of the religion and the world, and he states: ‘The Beloved Prophetصَلَّى اللهُ عَلَيْهِ وَاٰلِهٖ وَسَلَّمordered Sayyiduna Abu Bakr Siddiqueرَضِىَ الـلّٰـهُ عَـنْهُto lead the people in prayer. I was present at the time and I did not have any illness. In worldly matters, we were content with the selection of that individual whom the Noble Prophetصَلَّى اللهُ عَلَيْهِ وَاٰلِهٖ وَسَلَّم expressed his approval for in religious matters related to us.’ [Kanz ul ‘Umaal, Vol. 6, p. 230. Hadith. 35665]
When it came to the matter of the caliphate, Imam Haakimرَحْمَةُ الـلّٰـهِ عَـلَيْـهnarrates that Sayyiduna Ali Murtada, the lion of Allahرَضِىَ الـلّٰـهُ عَـنْهُ, said: ‘Listen attentively! It is Sayyiduna Abu Bakr Siddiqueرَضِىَ الـلّٰـهُ عَـنْهُwhom we consider worthy for the caliphate.’ [Al-Mustadrak, Vol. 4, p. 27, Hadith. 4519]
Sayyiduna Muhammad bin Hanafiyaرَضِىَ الـلّٰـهُ عَـنْهُstates that I asked my father (i.e. Sayyiduna Ali al-Murtadaرَضِىَ الـلّٰـهُ عَـنْهُ): ‘Who is the most superior from amongst the people after the Noble Prophetصَلَّى اللهُ عَلَيْهِ وَاٰلِهٖ وَسَلَّم? He replied: Abu Bakrرَضِىَ الـلّٰـهُ عَـنْهُ.’ [Bukhari, Vol. 2, p. 522, Hadith. 3671]
It is evident that you will only praise someone if you have love for them in your heart, and these pure individuals are protected from lying. Thus, we can never contemplate that they can gave false praises. Therefore, in light of all of these sayings of Sayyiduna Ali al-Murtadaرَضِىَ الـلّٰـهُ عَـنْهُ, it is clear that Sayyiduna Aliرَضِىَ الـلّٰـهُ عَـنْهُhad boundless love for Sayyiduna Siddique al-Akbarرَضِىَ الـلّٰـهُ عَـنْهُ, which spurred him to extol the virtues of Sayyiduna Abu Bakr Siddiqueرَضِىَ الـلّٰـهُ عَـنْهُ.
May Allah Almighty grant us true love for these two noble individuals, and for all of the companions and the Ahl al-Bait.
اٰمِیْن بِجَاہِ النَّبِیِّ الْاَمِیْنصَلَّی اللہ تَعَالٰی عَلَیْہِ وَاٰلہٖ وَسَلَّم
Reference: https://www.dawateislami.net/magazine/en/new-writers/excellence-of-siddiqe-akbar#_ftnref5