Is the question posed by the inquirer: "Is what is possessed by the right hand permissible fornication?" considered disbelief that expels one from the fold of Islam, given his knowledge of its permissibility, and that he did not intend to accuse the prophets and companions of unlawful fornication?

Cohabiting with a legally owned female slave is permissible and not considered 'zina' (fornication/adultery). Merely asking about its ruling is not an act of disbelief (kufr); rather, fearing disbelief indicates an aversion to it. It is advised to avoid obsessive thoughts (waswasa) regarding matters of disbelief and to turn away from them, engaging instead in seeking knowledge, inviting to Allah, and participating in social activities, while being wary of isolation.