Is stoning (Rajm) obligatory only upon a married person (Muhsan)?

Primary text

Stoning is obligatory solely upon the married person (Muhsan) by the consensus of the scholars, evidenced by the narration of Umar concerning the right of stoning for one who committed adultery while married, and the Prophet's statement that a Muslim's blood is not lawful except for three reasons, one of which is adultery after marriage (Zina ba'da Ihsan). Seven conditions are required for Ihsan.