Tafsir of Al-Ma'aarij 70:37

They are groups in dispersion, as Abu Ubaidah stated, citing the verse of Abid ibn al-Abras:

(They came rushing towards him until / They stood around his pulpit in groups [‘izīna])

Some have specified each group as being about three or four people. It is the plural of ‘izah, and its root is ‘izwah, derived from al-‘izz (pride/affiliation), because each group attributes itself and belongs to a different lineage than the other. Its last letter is a waw. It is also said that its last letter is a ha, and the original is ‘izhah, pluralized with waw and nun just as sunnah (year) and its counterparts are pluralized. The ‘ayn is vocalized with a kasra in the plural, and sometimes a damma. They said ‘izī on the pattern of fi‘īn, and they did not say ‘izāt.

‘Izīna is in the accusative case (nasb) as a circumstantial qualifier (hal) for "those who disbelieved," or for the pronoun in "rushing" (muhti‘īn)—incorporating one into the other.

"From the right" (‘an al-yamīn) is either linked to it because it carries the meaning of "dispersed," or it is linked to "rushing" (muhti‘īn), meaning: they are rushing from both directions. Alternatively, it is a circumstantial qualifier meaning "being situated on the right."

It is narrated that the Prophet (peace and blessings be upon him) was praying at the Kaaba and reciting the Quran, and the polytheists would gather around him in circles and scattered groups, listening and mocking his speech (peace and blessings be upon him), saying: "If these people enter Paradise as Muhammad (may Allah exalt his mention and grant him peace) says, then we shall surely enter it before them." Thus, this was revealed.

In some traditions, there is that which suggests it is better for believers not to sit in groups (‘izīna), for it is a custom of the Days of Ignorance (Jahiliyyah).