What did the early church fathers have to say about “eternal security” or “assurance of salvation”

I am trying to find out what the early church fathers had to say about “eternal security” or “assurance of salvation”. By that, I refer to the following Bible verses: >To Him who is able to keep you from falling and to present you before his glorious presence without fault and with great joy... (Jude 24) >...whoever believes in him shall not perish but have eternal life” (John 3:16) >My sheep listen to my voice; I know them, and they follow me. I give them eternal life, and they shall never perish; no-one can snatch them out of my hand (John 10:27-28). >And do not grieve the Holy Spirit of God, with whom you were sealed for the day of redemption (Ephesians 4:30) >For I am convinced that neither death nor life, neither angels nor demons, neither the present nor the future, nor any powers, neither height nor depth, nor anything else in all creation, will be able to separate us from the love of God that is in Christ Jesus our Lord (Romans 8:38-39). From verses such as these, Protestants understand that our eternal security is purchased by Christ, promised by the Father, and sealed by the Holy Spirit. This assurance is experienced by Christians who have the indwelling of the Holy Spirit, whose lives have been transformed as evidence of the new birth and who live for Christ Jesus and who are prepared to die for Him – born-again Christians. I say this not to promote a particular belief but to clarify what I mean by expressions like “eternal security” and “assurance of salvation”. Neither do I wish to enter into a discussion on the theology. I simply want to know what the early church fathers had to say on this subject.