Many earlier scholars, including the Lebanese Orientalist Joseph Simon Assemani and Edward René Hambye, believed he was a Jacobite, a member of the Syriac Orthodox Church.

[2] However, later research by Joseph Thekedathu, relying on additional documents found in the archives in the Vatican and Goa, has established further details of his life.

Eventually he requested to return to Syria, where he vowed he would bring the Syriac Orthodox Patriarch of Antioch, Ignatius Hidayat Aloho, into communion with Rome.

[5] There he made the acquaintance of the Capuchin monks, but afraid of being taken by the authorities and subjected to the Inquisition, he quietly boarded a Dutch vessel bound for Mylapore, which he reached most likely in August 1562.

However, the Jesuits extended considerable freedom to him, and allowed him to meet with Zachariah Cherrian Unni and two other members of the Saint Thomas Christian clergy.

Neill notes that however exaggerated these claims were, there is little reason to doubt that Ahatallah was at least a bishop, who had converted from the Syriac Orthodox Church to Catholicism.

[1] Ahatallah's appearance had joyed the Saint Thomas Christians, who had hoped for a new ecclesiastical leader to free them from the power of the Portuguese Padroado, which since the Synod of Diamper in 1599 had formally controlled church life in India.

Soon, however, the Jesuit Manoel de Leira secretly alerted the Portuguese authorities about Ahatallah's activities, and they put him on a ship headed for Cochin and Goa.

Supporting this, Anjilimoothil Ittithommen, one of the senior priests, produced two letters supposedly from Ahatallah that authorized the Archdeacon's consecration as bishop and detailed a ceremony facilitating it.

Thomas was consecrated by twelve priests, who laid one of the letters attributed to Ahatallah on his head, and afterward he acted fully as the metropolitan of Malankara.