Scholarly disagreement:

The Ḥanafīs and Mālikīs regard mani (semen) as impure, and they support this view with several arguments:

1. The ḥadiths that speak of washing it from the Messenger of Allah’s garment; washing, they say, is only prescribed for impurity.

2. It exits through the same passage as urine, so it must be washed with water like other impurities.

3. By analogy with the body’s other repellent wastes—urine and feces—because all of them are residues of digested food.

4. There is nothing to prevent the human being’s origin, namely semen, from being impure; those who deny this still hold that the clot (ʿalaqah) is impure because it is blood—and that too is an origin of the human.

5. The reports about scraping semen provide no proof of its purity; the scraping itself may be what purifies the garment while the semen remains impure—just as it is reported concerning filth on a sandal, whose purification is achieved with earth, which suffices in place of washing. That ruling does not imply that the filth itself is pure.

Moreover, had semen been pure, why would the Prophet ﷺ have ordered it to be scraped off? If it were pure, praying in a garment soiled with it would have been permissible without scraping. This is a summary of al-Ṭaḥāwī’s Sharḥ Maʿānī al-Āthār.

Imām al-Shāfiʿī and Aḥmad, however, maintain that semen is pure and not impure. They argue that it is no filthier than mucus or saliva, and they cite the following evidence:

1. The ḥadiths in which it is merely scraped or rubbed from the Prophet’s garment without washing; this is the strongest proof of its purity, for if it were impure such treatment would not suffice.

2. Semen is the very origin of the human being whom Allah has honored in a state of purity, so how could that origin be impure? As for the occasions when it was washed from his ﷺ garment, that does not indicate impurity; it was done for cleanliness, just as one removes saliva or mucus.