[Regarding Narrations about Satan and His Attachment to the Son of Adam]

Answer — and Allah is the Grantor of success and aid: What appears to me — and Allah knows best — is that filth and impurities, when they adhere to the human body, disturb one’s thoughts and unsettle inner tranquility. At that point, laziness and lethargy take hold of the body, and activity diminishes. Then Satan finds the path open to the human heart.
This is the opposite of cleanliness and purity, for they bring about energy, clarity of thought, sharpness of insight, and soundness of intellect. They eliminate lethargy and laziness and block the avenues through which Satan enters.
For this reason, Allah the Exalted referred to major ritual impurity as “the filth of Satan” in His saying: “And to remove from you the filth of Satan, and to strengthen your hearts and make firm thereby your feet.” [Al-Anfāl]

Source: Min Thimār al-ʿIlm wa al-Ḥikmah vol.3