The rationale is to expel any residual urine from the penis, thereby achieving greater cleanliness and complete removal of what remains.

Considering natr (shaking) and salt (drawing downward) to be recommended is the well-known view in Imam Aḥmad’s school; his later adherents followed it in their works. Al-Inṣāf states: “He explicitly affirmed this, and the Hanbalī scholars upheld it.”

Shaykh al-Islam (Ibn Taymiyyah) said, “Drawing or shaking the penis is an innovation; urine exits naturally of its own accord.” Shaykh ʿAbd al-Raḥmān al-Saʿdī remarked, “The sound position is that wiping and shaking are not recommended, because no authentic report establishes them and because they provoke waswasah (obsessive misgivings).” Al-Nawawī added, “One should not give free rein to such imaginings, for that only entrenches obsessive doubt in the heart.”