I think the "security" question depends on what we mean by salvation. My reconciliation has been entirely accomplished by another, is secure and cannot be undone. God will never have anything to hold against me. I do not believe it is up to me to hang on and keep myself acceptable to God (thank you God), just as it was not up to me to make myself acceptable. I guess if I persisted in apostasy, I would be living to myself, ignoring that I can only be real in relationship with God, and that would eventually destroy me. (Of course, as long as I consider the question at all, I am not apostate.)
A .......................... men !!!
JD
