The story of Abu Bakr al-Siddiq's conversion to Islam - from Ibn Ishaq's biography
Then Abu Bakr Al-Siddiq came to the Messenger of Allah, may Allah's prayers be upon him, and said: Is it true what Quraysh says, O Messenger of Allah, that you abandoned our gods, ridiculed our minds, and disbelieved in our fathers? The Prophet, may Allah's prayers be upon him, replied: O Abu Bakr, I am the Messenger of Allah and His Prophet, He sent me to convey His message and invite you to Allah with the truth, by Allah, I invite you to the truth, to Allah alone, who has no partner, and nothing is worshiped besides Him, and to ally with obedience to Him. The Messenger of Allah recited the Quran to him, so Abu Bakr did not flee, nor did he deny, so he became Muslim and disbelieved in idols, and renounced rivals, and acknowledged the right of Islam, and Abu Bakr returned, believing and confirming. This is from the biography of the Messenger of Allah, may Allah's prayers be upon him, as mentioned by Ibn Ishaq.