So if one confesses sin, they are doing so knowing that they will just do that sin some time next week, next month, or at some other time in the future?
The Bible plainly says all men are sinners. Not "were" sinners, as you suppose. We confess in order to be cleansed. And as Jesus had to teach ol' Peter in John 13, even though he was "clean", meaning saved, he still needed his feet cleaned to have fellowship with Jesus. Otherwise, Peter could have "no part" with Jesus. That's about fellowship obviously.
What is the purpose of confessing one's sin then?
I just told you. From the Bible. 1 Jn 1:9.
One is not really sorry if they are admitting to the fact that they will just immediately do so at some point in the future.
What is it about the words "immediately" and some point in the future" that aren't clear enough that they aren't equated at all? That's the continuing hang up that you present.
In Jesus' day, foot washing wasn't symbolic. It was functional. Animals shared the roads and paths with humans. So people got FECES all over their feet when they walked the roads and paths.
If you lived at that time, would you want anyone to track any of that stuff into your home? Hm? Of course not. You'd have a servant clean the feet of all visitors.
So, even though one would have had a bath before visiting, their feet would still need to be cleaned before entering the home for the purpose of fellowship. That was Jesus' point to Peter and the rest.
For is a man really sorry if he says to his wife that he cheated on her if he planned on cheating on her again at some point in the future? No. Of course not. Why do you think it is any different with God?...
I've explained this thoroughly. There is nothing more that I can do. But go ahead and knock yourself out with the most outlandish scenarios you can think of.
btw, I seriously doubt that anyone who does subscribe to eternal security would even come up with the wild ideas you bring up.
But since you do bring up extreme scenarios, it only shows that the real person that has been offended is you. And you don't want anyone to get away with anything. You want them in hell, right?
Well, God has a different plan for mankind. The plan is based on GRACE, something that the conditional security ilk have no idea about.
I've already shown the verses that teach that Christ died for all sin once for all. So even when a child of God sins after being saved, that sin was already covered by Christ's sacrifice.
It seems you're understanding of what the OT sacrifices were for is lacking.