First of all, the church we first go to was continuationist. We have seen the gift of prophecy (New Testament style) actually work. Second of all, we believe God is always working. We have seen deliverances work. We have seen too much proof that the Holy Spirit continues to work to disbelieve.
I don’t believe in OSAS, I believe we are saved by grace through faith in Jesus by the blood of Jesus, but because we have freewill, we can be “saved” and then reject Jesus. There are many examples of Christians who have apostatized, and I don’t believe they are saved, although they could be again if they wanted to, by returning as a prodigal. Furthermore, Paul states that grace is NOT a license to sin [Romans 6:1-2]. John the Baptist gave the baptism of repentance, and Jesus sent out people 2 by two to preach the message of repentance. God wants us to repent of our sins, and there are some very strong warnings about people who delight in or make a practice of sinning (these shall not inherit the kingdom of God). https://www.youtube.com/watch?v=eW_cklPNz-Ihttps://www.youtube.com/watch?v=Kwo7GTI1Ydg God looks at the heart. If you have a hard heart of an unrepentant sinner, with absolutely no effort to change your ways and trusting in OSAS, then it won’t turn out well for you. If you have an honest heart that tries your best to walk the walk and repent, I believe God will have mercy on such an individual even if they are still struggling in some areas of their walk.