According to Christians who believe that salvation can be lost, what is spiritual rebirth, what is eternal life and can salvation be regained?

According to Christians who believe that salvation can be lost: - What is eternal life? Is eternal life attained *now* (in this life / before death) or at the resurrection? - What is spiritual rebirth? When a Christian is born again, does he/she attain eternal life at that moment? - If salvation can be lost, can salvation be regained? Can we be saved multiple times? If so, would that mean that we can have multiple "born again experiences"? _____ **Related questions** - https://christianity.stackexchange.com/q/12097/50422 - https://christianity.stackexchange.com/q/89603/50422 - https://christianity.stackexchange.com/q/89602/50422