How too know somebody who does not have Jesus/HolySpirit living inside them (no slavation btw)... They drink alcohol, smoke, speak curses, isn't surrendered to Jesus Christ.
I speak from pure experience and I expose fake Jesus followeres because they ruin the idea of Jesus to none believers. It's why God hates fake the most, He hates lukewarms. Why would anybody want what somebody claims to have but doesn't have? I'm at a new job and people open up to me letting me know a certain person claims Jesus but smokes cigarettes thus doesn't believe he is sold out to Jesus which is truth. I've been there a month and my walk and talk allows them to notice the difference. See, when I surrendered my life to Jesus Christ, I received His Spirit which is clean, holy. When I smoked the next day He corrected me deep within, the same with alcohol. He lead me to scripture He tells me to stay sober and He helped me with it, which is a complete miracle especially that I was a dealer at one point who had access to free stuff that will get me high and or buzz. This is how you know Jesus Christ/Holy Spirit is real, by noticing someone changed by Him radically, which in this case is I an many more. So I preach to wake up the masses and to expose the lies from the ones who thought they were right witg God but are far from it because they choose to not surrender to Jesus Christ directly. I am simply being an example of the simplicity that is in Christ all while exposing the lies and the truth does hurt but it sets you free.
Jesus Christ is the Truth and the only way to the Father Creator.
Pride will keep you from surrendering your life to Jesus. Put off pride, surrender and leave your religion.