According to the Catholic Encyclopedia, Cosmas and Damian, familiar to us from the litany, were:
"Early Christian physicians and martyrs whose feast is celebrated on 27 September.
They were twins, born in Arabia, and practised the art of healing in the seaport Ægea, now Ayash (Ajass), on the Gulf of Iskanderun in Cilicia, Asia Minor, and attained a great reputation.
They accepted no pay for their services and were, therefore, called anargyroi, "the silverless". In this way they brought many to the Catholic Faith.
When the Diocletian persecution began, the Prefect Lysias had Cosmas and Damian arrested, and ordered them to recant. They remained constant under torture, in a miraculous manner suffered no injury from water, fire, air, nor on the cross, and were finally beheaded with the sword."