from his father, from the Prophet (ﷺ) (regarding this Ayah): 'And made them stick to the word of Taqwa (48:26).' He (ﷺ) said (the word is): "La Ilaha Illallah."
Jami` at-Tirmidhi Book 47, Hadith 317
← Previous Hadith that eighty people swooped down from the mountain of At-Tan'im to kill the Messenger of Allah (ﷺ) during Salat As-Subh, but he captured them and (later) let them go. So Allah revealed the Ayah: And it is He Who has withheld their hands from you and your hands from them (48:24).

Jami` at-Tirmidhi Book 47, Hadith 316 Next Hadith → "Al-Aqra' bin Habis arrived to meet the Prophet (ﷺ)" - he said - "so Abu Bakr said: 'O Messenger of Allah! Appoint him over his people.' 'Umar said: 'Do not appoint him O Messenger of Allah!' They continued talking before the Prophet (ﷺ) until they raised their voices. Abu Bakr said to 'Umar: 'You only wanted to contradict me.' So said: 'I did not want to contradict you.'" He said: "So this Ayah was revealed: 'O you who believe! Do not raise your voices above the voice of the Prophet (49:2).'" He said: "After that, when 'Umar spoke before the Prophet (ﷺ), his speech could not be heard until he told him he could not understand him." He (one of the narrators) said: "And Ibn Az-Zubair did not mention his grandfather" meaning Abu Bakr.

Jami` at-Tirmidhi Book 47, Hadith 318