Qays al-Ghassani, also known as 'Abd al-Masih, was a medieval Eastern Orthodox martyr.
His death was recorded in a 10th-century manuscript now belonging to Saint Catherine's Monastery, on Mount Sinai.
Living in the 9th century CE he fell in with a group of Muslims who practised raiding, and while in their company converted to Islam.
However, after some thirteen years, while at Baalbek, he heard the Gospel being read by a priest; he was reminded of his past life as a Christian, and became convinced of the error of his ways.
He served as steward, then superior, at Mount Sinai, and during this time he needed to travel to Ramla on a legal matter.