Martyrs Manuel, Sabael, and Ismael of Persia (362)

"The holy Martyrs Manuel, Sabel, and Ishmael, Persians by race and brethren according to the flesh, were sent by the Persian King as ambassadors to Julian the Apostate to negotiate a peace treaty. While with him at a place near Chalcedon, they refused to join him in offering sacrifice to his idols. Scorning the immunity universally accorded ambassadors, he had them slain in the year 362. This was a cause of the war with Persia in which Julian perished miserably the following year." (Great Horologion)