Caesarius of Nazianzus was born in 331. He was the younger son of Gregory the Elder, the bishop of Nazianzus, and his wife Nonna. His older brother was Saint Gregory of Nazianzus. He probably studied at Caesarea Mazaca in Cappadocia. He was preparing to attend an elite school in Alexandria, Egypt. He studied geometry and astronomy, but he excelled in medicine where he was at the top of his class.
In 355, he went to the capital, Constantinople with a great reputation for his medical skills. His brother Gregory was there returning from a trip to Athens. Caesarius gave up a lucrative and honorable post to return home with Gregory. However, he missed Constantinople too much and he returned as a physician to the court of Constantius II. His family was not happy about this because he returned to paganism. Caesarius decided his faith was more important than the favor of the emperor.
When Valens became the emperor, Caesarius was put in charge of the treasury and tax collection. Gregory having just survived an earthquake in Nicaea, wrote to Caesarius, pleading for him to leave his political position and withdraw to the religious life. In 368, Caesarius was suddenly killed by the widespread plague which followed the earthquake. Like many of his time he had only recently received baptism After his death, his very considerable estate was rapidly pillaged by servants and creditors. Gregory insisted that what remained of the estate be distributed to the poor and to surviving relatives.