I like reading your posts / discussing with you even though we disagree 100%
. You sound honest and patient.
I wouldnt use 1 John 5:13 without 1 Cor 12:3 as many have heard and believed, but don't accept Jesus. A revelation from the Holy Spirit is needed for us to call Jesus Lord, as was the case with Peter. The most convincing proof I feel that you can raise from scripture with your way of thinking is that we hear God's voice and have the witness of the Holy Spirit John 10:27, 1 Corinthians 12:3.
In every religion, people have an emotional experience with a god. So being 100% confident in our salvation purely off the voice / feeling we have from God is not wise. We need to look at our fruits Matt 7:16
'You will know them by their fruits'. Now we know that none of us are living without sin. Hence we are all repenting and asking for forgiveness daily so we follow Phil 2:12 work out your salvation with fear and trembling and 1 Cor 10:12 Therefore let him who thinks he stands take heed that he does not fall.
We can have confidence that we are saved, I am not disputing that, but the confidence we have is from / after examining ourselves, our actions and thoughts. 2 Cor 13:5.
None of us can truthfully say we have never feared missing the rapture after being in sin .