Imam Junayd al-Baghdadi (d. 910) was born in Nihawand in Persia, but his family settled in Baghdad where he studied Islamic Law according to the school of Imam Shafi'i, and eventually became a chief judge in Baghdad. In Sufi discipline, he was the close follower of his uncle, Shaykh as-Sari as-Saqti. Although he was the spiritual master of Mansur al-Hallaj, he was obliged, in his capacity as chief judge of Baghdad, to sign the warrant authorizing the execution of al-Hallaj. On it he wrote: 'Under Islamic Law, he is guilty. According to the Inner Reality, God knows.'
Source : Nuradeen.com