Among the best of these attempts at explanation are two possibilities.

The first: a male infant possesses an innate bodily heat greater than that of a female, a heat that “cooks” the milk he consumes and refines the waste that leaves his body. Added to this excess heat is the fact that his food is extremely light, consisting only of milk. A girl, on the other hand, does not have this moderating heat. This is supported by the Prophet’s restriction of the concession to cases in which the child’s only food is milk.

The second: a boy is, as a rule, more coveted than a girl, so he is carried about and moved from place to place far more often. Consequently, his impurity is more likely to come into direct contact with people, causing hardship and embarrassment. The Law therefore grants a relaxation with regard to his impurity, which accords with the well-known leniency of the Sharia.

A general legal maxim states: “Hardship begets ease.”

Nevertheless, some scholars have treated this ruling as purely devotional (taʿabbudī), whose reason is not meant to be grasped; Allah knows best what He intended.

How to purify ground soiled by urine

Anas ibn Malik (may Allah be pleased with him) reported: “A Bedouin entered and urinated in one corner of the mosque. The people rebuked him, but the Prophet ﷺ stopped them. When the man had finished, the Prophet ﷺ called for a bucket full of water and it was poured over the area.”

Explanatory notes on the wording

1 – aʿrābī: derived from aʿrāb (the Bedouins, desert dwellers); the nisbah is to the plural, not the singular.
2 – fī ṭāʾifati al-masjid: in one section of the mosque.
3 – fazajara-hu an-nās: the people scolded him.
4 – bi-dhanūbin min māʾ: with a dhanūb—a bucket filled with water; it is not called dhanūb unless it contains water. fa-uhriqa ʿalay-hi: originally urīqa ʿalay-hi (“it was poured over it”); the initial hamzah was changed to a hāʾ, becoming fuhriqa, then another hamzah was added, yielding fa-uhriqa. The hāʾ is quiescent and the verb is passive.

Overall meaning

Bedouins are generally known for their roughness and lack of learning because living far from the centers of knowledge keeps them from acquiring what Allah revealed to His Messenger.