According to Orthodox tradition, Saint Onesiphorus was one of the seventy disciples chosen and sent by Jesus to preach.

Both the Orthodox and Roman Catholic churches hold that he died a martyr in the city of Parium on the shores of the Hellespont.

Paul's reference to Onesiphorus, along with 2 Maccabees 12:40–46, is cited by Catholics as one of the early examples of prayer for the dead,[6] while some Protestants opposing this practice reject such an interpretation.

[7] Remarkably, Onesiphorus made a 1000-mile journey, over three large bodies of water from one continent to another (from Ephesus (today: Turkey) to Rome (today: Italy)) — to specifically search for and find Paul in prison, so as to comfort him.

[9] He should not be confused with the Onesiphorus of Ephesus who was martyred with Porphyrius during the Diocletian persecution, and is commemorated on November 9.