Do you see what I see?
This is one of those scriptures that's not as it appears at first glance. It may seem as if it's suggesting that one loses their salvation, but it's not. If you take a really close look at it, it's actually confirming the security of a believer
.........
Christ's ONE sacrifice is sufficient to cleanse us of ALL unrighteousness. We are born of the spirit ONE time, not multiple times.
This scripture is showing how impossible it is to be saved, then unsaved, then saved again.... because that ONE sacrifice was sufficient to cleanse us the first time!! So to suggest our salvation can be "undone" would be putting Christ to open shame, suggesting that His sacrifice was not sufficient!!! So in other words, "crucifying him afresh" each time by suggesting that He was not able to save us completely the first time, that He must be crucified a second and third time.
It's impossible to
renew them again (because we were already renewed) so how can it possibly happen again, because salvation happens ONE time. It cannot happen a second time. Christ was crucified ONCE and it was sufficient.
This is confirming the security of the believer, not suggesting that salvation is undone in any way!