Three leaders of Quraysh, Abu Sufyan ibn Harb, Abu Jahal ibn Hisham and al-Akhnas ibn Shurayq, each went out alone one night to listen secretly outside the Prophet ﷺ's house. He was praying at night and reciting the Qur'an. None of them knew that the others were there, and they listened until dawn. On the way home they met on the road and blamed one another, saying they must not come back. The same thing happened on the second night, and again on the third. On the third morning they made a firm promise never to return.
Later that morning, al-Akhnas went to Abu Sufyan and asked him privately what he thought of what he had heard. Abu Sufyan said he had understood some of it but not all of it. Al-Akhnas then asked Abu Jahal the same question. Abu Jahal said that his clan had always competed with the Prophet ﷺ's clan for honour. Now that they claimed a prophet who received revelation from heaven, there was no way to compete with them, and he swore he would never believe in him.
Other events recorded around the same time. Their order within the year is not established; use the storyline above for the sequence.
Tell me, O Abu Hanzala, what do you think of what you have heard from Muhammad ﷺ?
Said the morning after the third night of secretly listening to the Prophet ﷺ recite, once the three had agreed among themselves never to return.
O Abu al-Hakam, what do you think of what you have heard from Muhammad ﷺ?
Said after leaving Abu Sufyan's house and going on to Abu Jahal's, the same morning.
What did you hear?
We and Banu Abd Manaf competed for honor and position: they fed people, so we fed people; they engaged in battle, so we engaged in battle; they gave, so we gave; until we were neck and neck like race horses. Then they said, "We have a prophet among us who receives revelation from heaven"? How could we compete with that! By Allah, we will never believe in him.