I can’t decide if you are right that we have eternal security, or if (another website) is right and we can lose it for bad behavior. If it does turn out that you are wrong, that is a terrible burden to bear.
The question isn’t whether I’m right or someone else is right, but whether God has been truthful or not. And since I’m taking Him at His most clearly stated unconditional word, I bear no burden. It’s those who refuse to trust Him who will have the explaining to do.
The site you sent me to takes verses out of context from here and there to support their views without regard for the fact that in doing so they have God saying something in one place and something entirely different in another. Seems to me that one who puts himself forward as a teacher would have a scary time explaining to God why he did that. That’s the burden I don’t want to bear. James 3:1 says, Not many of you should presume to be teachers, my brothers, because you know that we who teach will be judged more strictly.
Lots of people debate the meanings of Hebrews 6, 10, 12 and other obscure passages, but I’ve never found anyone who could mount a convincing argument against Ephesians 1:13-14 or 2 Cor. 1:21-22 or other passages I’ve quoted. They’re just too clear. To deny OSAS you have to ignore them.