Because of Christ's sacrifice on our behalf, we are pleasing to God because we are a new creation. However, we must always ask if He is pleased with the way we conduct our lives. Just as saints of the past like Enoch, we must deny the flesh and follow God whole heartedly in this present evil world.
Paul does not question the salvation of the believers, but rather whether they have a living faith. While it is true that saving faith and living faith are different, all Christians need to be concerned not only about their walk with the Lord, but about the walk of the Lord with others in the body of Christ.
Happy Mother's Day! Whether or not we are mothers, we are an example to those around us. If we tell people we are believers, we need to walk and act like a believer. Our example may give us a closed or an open door to the gospel, depending on how we live our lives.