7. The Holy Spirit, Our Seal – God gives the Holy Spirit to every believer when we get saved  as the earnest (down payment ) of his promise to take us to heaven and give us our inheritance  (see #4). We can only be unsaved if we do not have the Holy Spirit , which means we would have to lose the Holy Spirit to get lost again; but the Bible says we are SEALED by and with the Holy Spirit UNTIL the day of redemption . The Holy Spirit can be quenched  or grieved  but not lost.
8. The Sinful Believer and the False Christian – We will not be perfect until we get to heaven, and we may be disobedient, but we cannot lose our salvation. We can still fall, but not so as to be eternally lost, for the Lord upholds us . We are still tempted and tried , as Jesus was , but only for the purpose of strengthening us and making us more of what the Lord wants us to be. Our works may not stand the fiery test of the judgement  but our salvation will .
Not all who claim to be saved are. Not all church members are saved. If they are saved, they will eventually show a change and false professors of Christ eventually fall away . Just make sure you are trusting ONLY Jesus  and HIS righteousness  to get you to heaven, not YOUR faith or a prayer or work(s), and you believe (trust ) to the “saving of the soul” .
9. Misapplication of Scripture / Rightly Dividing the Word – One should not twist Scripture  talking about the Old Testament saints, Tribulation saints, or the losing of a ministry, testimony, nation, or life and try to make it prove a sinner forgiven by the grace of God through Christ’s blood can lose his salvation. The Word of God must be “rightly divided”  or it can be “wrested unto your own destruction” .