Today is the commemoration of St. Polycarp of Smyrna, who had been ordained by St. John the Apostle. He was killed in his eighties, probably a bit after AD 150; according to tradition, he was killed by being burned alive.
From the letter of Polycarp to the Philippians (chapter 3), probably written around AD 117, a bit after the death of St. Ignatius of Antioch, with whom Polycarp corresponded:
I am writing you these comments about righteousness, brothers, not on my own initiative but because you invited me to do so. For neither I nor anyone like me can keep pace with the wisdom of the blessed and glorious Paul. When he was with you in the presence of the people of that time, he accurately and reliably taught the word concerning the truth. And when he was absent he wrote you letters; if you study them carefully, you will be able to build yourselves up in the faith that has been given to you, which is the mother of us all, while hope follows and love for God and Christ and for our neighbor leads the way. For if anyone is occupied with these, that person has fulfilled the commandment of righteousness, for whoever has love is far from all sin.
[Michael W. Holmes, ed. and tr., The Apostolic Fathers, 3rd edition, Baker Academic (Grand Rapids, MI: 2007) 283-284.]