Concerning whom was this verse revealed?

Imām Ibn al-Jawzī (d. 597 AH / 1201 CE) summarized the scholars' opinions in his book "Zād al-Masīr" as follows:

1. It was revealed regarding ʿAbd Allāh ibn Ubayy and his companions. [Ibn ʿAbbās]
2. It was revealed regarding the hypocrites and others from the People of the Book who used to pretend to have faith in front of the Prophet (ﷺ) while they would display the opposite when meeting with their leaders. [Al-Ḥasan]