Abgar V was a 1st century king of Edessa who wrote to Jesus asking for healing. Jesus' reply that he would send one of his apostles to Abgar to heal him and preach the Gospel to him was accompanied by an imprint of his face on a piece of cloth, which has come to be known as the Icon Made Without Hands. The Apostle Thaddeus eventually did visit Abgar, healing him and converting him to the Christian faith.
The story is recorded in the Ecclesiastical History of Eusebius of Caesarea and is regarded by some as legendary.