There are many names mentioned in the New Testament and one of them is Sosthenes. While that name is only included twice in the entire Bible, he is regarded as a "brother" to St. Paul the Apostle.
The first time we encounter this name is in the book of Acts.
But when Gallio was proconsul of Achaia, the Jews made a united attack upon Paul and brought him before the tribunal, saying, “This man is persuading men to worship God contrary to the law.” But when Paul was about to open his mouth, Gallio said to the Jews, “If it were a matter of wrongdoing or vicious crime, I should have reason to bear with you, O Jews; but since it is a matter of questions about words and names and your own law, see to it yourselves; I refuse to be a judge of these things.” And he drove them from the tribunal. And they all seized Sosthenes, the ruler of the synagogue, and beat him in front of the tribunal.
This passage makes Sosthenes the ruler of the synagogue in Corinth.
Later in St. Paul's letter to the Corinthians, Sosthenes is noted as a co-author of the letter.
Paul, called by the will of God to be an apostle of Christ Jesus, and our brother Sosthenes, To the church of God which is at Corinth.
It's possible that these two people are the same, but historians tend to disagree whether or not they refer to the same person.
Outside of the Bible, tradition claims that Sosthenes was one of the 70 disciples of Jesus.
The Eastern Church celebrates St. Sosthenes on a variety of days each year, and refers to him in their liturgy.
Holy Apostle Sosthenes of the Seventy;
Entreat the Merciful;
To Grant Our Souls Forgiveness of Transgressions.
While we may not know much about Sosthenes, if St. Paul regarded him as a "brother," and entrusted him with co-writing a letter to the Church in Cornith, then he may have been a worthy disciple of Christ.