Mukhtasar Bukhari

Sayyiduna Ibn Abbas (may Allah be pleased with them both) said that the Prophet Muhammad (peace and blessings be upon him) said: "Allah has written for the children of Adam their share of adultery, which they will inevitably commit. The adultery of the eye is looking (at what is forbidden), the adultery of the tongue is speaking (about it), and the soul desires and wishes, and the private part either confirms that desire or denies it."