Muslim

Hadith Commentary:
This was a practice of martial skills.
Hazrat Umar (radi Allahu anhu) considered it contrary to proper etiquette in the presence of the Prophet, but the Messenger of Allah (sallallahu alayhi wa sallam) encouraged the Abyssinian warriors and allowed their practice to continue.
In the era of Prophethood, not only dissemination and propagation, but all administrative affairs of the community—even the work of an office—were conducted from the mosque itself.
It was the early period of Islam; conveniences as available today did not exist, so the mosque was used as the center of the community for communal affairs.
Even today, mosques can be used in this manner for Islamic communal matters.
And in this is sufficient guidance for one who has understanding.

Hadith Commentary:
➊
In the hadith, "playing" does not refer to mere amusement or entertainment, but rather to martial exercises.
In another hadith, it is stated that no play is befitting for a Muslim except for three:
First, training one’s horse for battle; second, playing with one’s wife; third, practicing archery with a bow.
(Sunan Abi Dawud, Book of Jihad, Hadith: 2513)
In any case, a Muslim should engage with weapons of war and be familiar with modern weaponry.
One never knows when there may be a need for them.
➋
Umar radi Allahu anhu considered this to be contrary to decorum, but the Messenger of Allah sallallahu alayhi wa sallam, encouraging the Abyssinian (Habashi) warriors, instructed that this martial exercise should continue.
(Fath al-Bari: 6/114)

1597. Commentary:

➊ The mosque is not for play and amusement, but since this game was not frivolous—instead, they were playing with spears and javelins, which are means of strengthening the Muslims’ jihadi (military) power—it was therefore permitted in the mosque. Otherwise, football, cricket, etc., cannot be played in the mosque, as they are merely amusement or, at most, for physical exercise. Those who play them do not have a “jihadi” (military) intention.

➋ “Banu Arfidah” is a title of the Abyssinians or a reference to their ancestor.