Beloved: I have experienced much joy and encouragement from your love, because the hearts of the holy ones have been refreshed by you, brother. (Phmn 7-20)
https://bible.usccb.org/bible/readings/111022.cfm
The church rarely uses the word “great” of any saint, but Saint Leo (400-461) was the first pope to receive this honorific. He was pope from 440-461. In his homily for Christmas Day, Pope Leo said: “Christian, remember your dignity, and now that you share in God's own nature, do not return by sin to your former base condition. Bear in mind who is your head and of whose body you are a member. Do not forget that you have been rescued from the power of darkness and brought into the light of God's kingdom. Through the sacrament of baptism you have become a temple of the Holy Spirit.”