Andronicus and Junia
Greet Andronicus and Junia, my relatives who were in prison with me; they are prominent among the apostles, and they were in Christ before I was. (Rom 16:7)Andronicus and Junia were almost certainly from Palestine because they were Jews who were in Christ before Paul. Junia was a Latin female name. It is very probable that Junia went by another name in Palestine because
a) Only 4.1% of occurrences of Jewish female names in Palestine are Latin.(2)
b) The name Junia, while common in Rome, was particularly rare in the east.
The table below shows all the early Christians with recorded names belonging to more than one language. Barnabas and Luke have been added to complete the list of apostles to gentile territories. It can be seen that the name pairs fall into two categories.
1) There are those who were given a new name because of its meaning, and such names are shown in bold. The name Junia does not appear to belong to this category since it has no special meaning and there is little evidence that the early Christians employed Latin names for this purpose.
2) All the others in the table had names that had a phonetic resemblance to each other. We need not suppose that John Mark was an exception since Mark is a praenomen and he probably also had a cognomen, which may have been phonetically similar to his Semitic name, John.
The table shows that Latin names (rather than Greek) dominate those who evangelised gentile lands (I include Jesus Justus, though he was fictional). This is likely because missionaries needed the legal protection of Roman citizenship to do their dangerous work. See here. Now, Junia was a Latin name, so fits the pattern, but what about Andronicus, which was a Greek name? The other travelling missionaries who were known in the diaspora by non-Latin names are Barnabas, Timothy and Peter, and it is striking that all three were probably new names given in recognition of their roles in the church. This phenomenon of new name giving was more widespread than is often supposed and in most (all?) cases the new name was given to a church host or benefactor. See here. The name Andronicus is formed from ἀνδρὸς (of man) and νίκη (victory), and can be translated "victory of a man". The name may therefore have been given to him for his role as benefactor, in much the same way that the Greek names Stephanas (crowned), Sosthenes (saving strength), and Peter (rock) were given to those hosts/benefactors.
So, in our search for Andronicus and Junia we are looking for people who meet the following criteria:
1) They were a male/female partnership.
2) Both were Jews.
3) Both were in Christ before Paul.
4) The man could well have been a benefactor.
5) They were prominent in the church.
6) The woman was probably called Joanna.
7) They had, or could attain, Roman citizenship.
Joanna and Chuza
Soon afterwards he went on through cities and villages, proclaiming and bringing the good news of the kingdom of God, and the twelve with him and some women who had been cured of evil spirits and infirmities: Mary, called the Magdalene, from whom seven demons had gone out, and Joanna, the wife of Herod's steward Chuza, and Sussana, and may others, who provided for them out of their resources. (Luke 8:1-3)
Now it was Mary Magdalene, Joanna, Mary the mother of James and the other women with them who told this to the apostles (Luke 24:10)Joanna and Chuza meet the above criteria for Junia and Andronicus:
1) They were a female/male partnership.
2) They were almost certainly both Jews (because of their location and Joanna's name)
3) Joanna's financial support of the Jesus movement is easier to explain if Chuza was also a disciple, since husbands generally controlled the resources. Given his position as Herod's steward, he may have needed to keep his support of Jesus secret (compare Joseph of Arimathea, who was a member of the Council (Mark 15:43) and a secret disciple (John 19:38)). If Chuza was indeed a disciple at that time, he and Joanna, like Andronicus and Junia, were in Christ before Paul.
4) Chuza, if indeed a disciple, would have been a benefactor of the church, and could then have been given an appropriate Greek name, such as Andronicus.
5) Luke mentions Joanna and Chuza by name, perhaps because they became prominent apostles who were known to some of his audience.
6) Joanna would likely have taken the name Junia if she needed a Latin name.
7) Bauckham has shown that Chuza was very wealthy. He and Joanna, if they were not already Roman citizens, would be able to purchase Roman citizenship (which afforded them the necessary legal protection for the dangerous work of evangelism).
Conclusion
The name Joanna was held by just 3% of Jewish women in Palestine. Junia was probably a prominent early disciple called Joanna. In my judgement there was probably only one such individual, the Joanna of Luke's gospel.
It may be objected that Junia's partner was Andronicus, whereas Joanna's parter was Chuza. However, I have reversed this argument by showing that Andronicus's Greek name implies that he was a wealthy individual with an earlier name, and this would fit Chuza nicely.
Luke's source for his information on Joanna, and indeed much of his gospel, may have been Joanna-Junia herself, since they would have met in Rome.
Notes
(1) Richard Bauckham, Gospel Women (2002) 165-186.
(2) Tal Ilan, Lexicon of Jewish Names in Late Antiquity Part I Palestine 330 BCE-200 CE (2002) 55.
(3) See Ilan's volumes.
(4) At least from searches of Latin female names in Trismegistos. I will search other sources when it is safe to visit libraries. The next best candidate is perhaps Iuliana.