The text provides some kind of circumstantial evidence he might have.
Nevertheless, other evidence suggests he hadn't died yet.
6 Septembris In Palaestina sancti Zachariae Prophetae, qui, de Chaldaea senex in patriam reversus, ibique defunctus, juxta Aggaeum Prophetam conditus jacet.
In Hellesponto sancti Onesiphori, Apostolorum discipuli, cujus meminit sanctus Paulus ad Timotheum scribens. Ipse autem Onesiphorus ibidem, una cum sancto Porphyrio, jussu Hadriani Proconsulis acriter verberatus et a ferocibus raptatus equis, spiritum Deo reddidit. ...
Iussi Hadriani Proconsulis? Does that mean some other Hadrian, or does that mean Emperor Hadrian while he was yet only a proconsul?
In the latter case, Onesiphorus cannot have been dead before Saint Paul. Hadrian (/ˈheɪdriən/; Latin: Publius Aelius Hadrianus Augustus;[note 1][note 2] 24 January 76 – 10 July 138) was Roman emperor from 117 to 138.
He cannot have been proconsul until he was born, and he was born after Saint Paul.
- Catholic Online : St. Onesiphorus
- September 6
- Martyr with Porphyrius. Onesiphorus was mentioned in St. Paul's Second Letter to Timothy. According to tradition, they went to Spain in the footsteps of St. Paul and then suffered martyrdom on the Hellespont, under Emperor Domitian. They were tied to wild horses and torn to pieces. Porphyrius was said to be a member of Onesiphorus' household.
On the other hand, an Emperor born in 76 can hardly have been proconsul in 81 either. So, no argument from Hadrian's life.
On the "first hand again"*, 81 is also after St Paul's death. So, when St Paul prayed, St Onesiphorus was not yet dead.
However, he could have been missing, even suspected already dead. And St Paul could have used a prayer which would be equally appropriate if preparing for his Christian death, perhaps even as a martyr - which is what he became.
That said, the argument from II Maccabees is still sufficient even for those not accepting it as canonic. Author was not a Sadducee. And he showed that non-Sadducee Jews were praying for the dead. So did Israelites of North Kingdom - if you read Tobit. There even one deed associated with indulgences for the dead is named, namely offering meals to the poor who pray for the dead (only righteous poor being welcome, in the eyes of the older Tobias).
Hans Georg Lundahl
* How do you say when you counter something you said with "on the other hand"? I have used "on the third hand", but there is no such thing on a human body. One could imagine using "on the OTHER hand" with extra emphasis on other too ...? ** Greeks celebrate him tomorrow - or thirteen days later.