This is from a Greek icon and reads: Saint Ioasaf son of the Indian King Avenir
There are links at the bottom of the wiki article which take you to an English translation of the hagiography of Saint Ioasaf. Basically it is just a Christianised version of the life of Siddhartha Gautama with the Buddha finding salvation by turning to Christ. It overlooks the minor detail that Christ came 500 years after the Buddha but anyway... a good try nonetheless!Ioasaph (Georgian Iodasaph, Arabic Yūdhasaf or Būdhasaf) is derived from the Sanskrit Bodhisattva. The Sanskrit word was changed to Bodisav in Persian texts in the 6th or 7th century, then to Budhasaf or Yudasaf in an 8th-century Arabic document (possibly by Arabic initial "b" ﺑ changed to "y" ﻳ by duplication of a dot in handwriting). This became Iodasaph in Georgia in the 10th century, and that name was adapted as Ioasaph in Greece in the 11th century, and then as Iosaphat or Josaphat in Latin.