It is generally assumed that Junia was his wife, but they could have been brother and sister, or father and daughter, or no close relation to each other, but to Paul as kinsmen.
His references to the couple's imprisonment with him and to the time of their conversion relative to his own would give him no interest in deferring to the opinion of others as a source of credentials.
The Staggs conclude that both the context and the content of this verse require that it be read naturally as Paul's commendation of Andronicus and Junia as being remarkable Christian workers and "apostles" alongside Silas, Timothy, and others given that title in the early Church.
The tradition holds that they were capable of performing miracles, by which they drove out demons and healed many of sickness and disease.
The Catholic archbishopric of Moravia was originally established by Pope Nicholas I in the 9th century as a revival of the see founded by Andronicus.