These verses say literally nothing about the issue of prayer to or for the dead. However, here from 2 Timothy:
[16] May the Lord grant mercy to the household of Onesiph'orus, for he often refreshed me; he was not ashamed of my chains,
[17] but when he arrived in Rome he searched for me eagerly and found me --
[18] may the Lord grant him to find mercy from the Lord on that Day -- and you well know all the service he rendered at Ephesus...
Notice that Paul is appealing to God for the mercy of someone who has died.
Again, we know that the early church did believe that the living could pray for the dead and ask them to intercede, and that this was also done by Jews preceding Jesus as well as what shows up in 2 Maccabees 12, regardless as to whether you don't accept that as being part of the canon. Either way, it was done.
If you add the word “dead” then it will sound like Paul was praying for the “dead”, but if you add in the words “not there” then it will sound like Paul was asking God on behalf of Onesiphorus who was “not there” but was still alive at that time.
Remember Paul was writing from Rome to Timothy so he would NOT know where Onesiphorus was. Paul was just comparing Onesiphorus faithfulness with the two apostates, Phygelus and Hermogenes.
If you read verse 15, “You know that everyone in the province of Asia has deserted me, including Phygelus and Hermogenes.” 2 Timothy 1:15
Then comparing Phygelus and Hermogenes to Onesiphorus, Paul writes in 2 Timothy 1:16: “May the Lord show mercy to the household of Onesiphorus,” Actually the word is “house” means the family of Onesiphorus including himself. It does not mean Onesiphorus is dead at all.
WHY?
Was it because Onesiphorus was nothing like Phygelus and Hermogenes both deserted Paul while he was in Asia? Yes!
“because he often refreshed me and was not ashamed of my chains." –verse 16, unlike Phygelus and Hermognenes, right?
Then Paul continued in verse 17:
“On the contrary,” Paul writes, Onesiphorus was nothing like these two guys because
“when he was in Rome, he searched hard for me until he found me.” –verse 17.
“when he was in Rome,” means it happened in the past.
For example:
“When John Doe was in Germany” it does not mean we are talking about a dead person, right?
“When Onesiphorus was in Rome” means it happened in the past and not necessarily dead.
So, in verse 18 Paul writes:
“May the Lord grant that he will find mercy from the Lord on that day!”
Why? Because of all the help Onesiphorus [meaning a help-bringer] have brought Paul.
Then Paul continued in verse 18:
“You know very well in how many ways he helped me in Ephesus.” 2 Timothy 1:18
As Paul was writing this letter from Rome to Timothy he was making the comparison between
Onesiphorus faithfulness and the
two apostates Phygelus and Hermogenes that Timothy should learn from and then we can read in the following chapter 2 Timothy 2:1
“You then, my son, be strong in the grace that is in Christ Jesus.”
Just like who? Onesiphorus, that’s who.
These verses are NOT about praying for or to the dead. You guys would twist the word of God so you could justify your praying to/for the dead.