Clement I
Clement I of Rome (not to be confused with later Popes Clement or Clement of Alexandria (d ~215 AD), is often understood to be the person named Clement called out in the Biblical book of Philippians.
Indeed, true comrade, I ask you
also to help these women who have shared my struggle in the cause of the gospel,
together with Clement also, and the rest of my fellow workers, whose names are
in the book of life. – Philippians 4:3
While we see Clement as a faithful member of the church in Philippi in the Scripture, Clement is subsequently named in different lists as either the second or fourth bishop of Rome. Church tradition holds that he was specifically consecrated by Peter for the role, serving from AD 88 to AD 99.
While a number of writings are attributed to Clement, the only one which can be said with certainty to be from the pen of this church father is a letter to the church in Corinth. This letter is considered to be the earliest Christian document outside of the New Testament.
Clement’s letter to the church in Corinth indicates that the Corinthians has repented of the divisiveness shown in Paul’s letters to the same churches. However, they were beginning to fragment again, even worse than when Paul wrote to them, to the point of expelling two of their elders. It is a long letter (65 chapters containing over 14,000 words) full of Biblical teaching and exhortations to humility and brotherly love. He writes of the martyrdom of both Peter and Paul as well as others who gave their lives for the faith. He speaks of church government, and gives specific counsel to reinstate the two elders who had been expelled.
Chapter 23 begins a great dissertation on the Resurrection of Christ. He brings the example of the Phoenix (a single bird he attributed to the Arabian area), a bird which was said to live exactly 500 years, then return to Egypt to die by burning itself to death. Then, from the ashes a worm appeared which grew into the next phoenix. Apparently, Clement believed the story to be true and used it as a beautiful illustration of the resurrection.
Clement was arrested under the persecution of the Roman Emperor Trajan and set to work in a stone quarry on the Crimean peninsula. There is a legend about him during this time that they had a severe shortage of water. Clement prayed for water and, according to the legend, had a vision of a lamb on a hill. Taking a pickaxe, he walked up to where the lamb was, struck the ground with the pickaxe, and a clear gusher of water flowed to quench the thirst of the prisoners.
Clement was martyred by being tied to an anchor and thrown into the Black Sea.
https://en.wikipedia.org/wiki/Pope_Clement_I#Epistle_of_Clement
https://www.christian-history.org/clement-of-rome.html
https://www.newadvent.org/fathers/1010.htm