The Zina (adultery) of the eye is the (lustful) look,
the Zina of the ears is the listening (to voluptuous talk),
the Zina of the tongue is (the licentious) speech,
the Zina of the hand is the (lustful) grip,
the Zina of the feet is the walking (to the place where one intends to commit Zina)
[Recorded by both Al-Bukhari and Muslim]
The son of Abu Said al-Khudri reported on the authority of his father that Allaah’s Messenger (sallAllaahu alayhi wa sallam) said:
When one of you yawns, he should keep his mouth shut with the help of his hand, for it is the devil that enters therein.