If I believe the gospel, does the Holy Spirit live in me?
Yes. When a person believes the gospel—the truth that Christ died for all and rose again—the Holy Spirit comes to live within them. His indwelling presence shows they are not in the flesh but are a believer in Christ, forgiven, a new creation, and no longer under condemnation.
Les explains that Romans 8 and Ephesians 1 teach the same truth: if the indwelling Holy Spirit is evident, you are not in the flesh or under Adam’s control. He says if you have believed the Gospel and its truth, the Holy Spirit is in you; and if the Holy Spirit is in you, you are a believer. The conclusion is that you are in Christ, there is now no condemnation, Paul says you have been forgiven all trespasses, and you are a new creation. Les then points to 2 Corinthians 5:14-15, where the love of Christ constrains us because one died for all—every human being—and rose again, which is the Gospel.
But ye are not in the flesh, but in the Spirit, if so be that the Spirit of God dwell in you. Now if any man have not the Spirit of Christ, he is none of his.