Salvation is... assured through the Holy Spirit
Every believer receives the Holy Spirit as a "deposit" of God's promise (Ephesians 1:13-14). The Holy Spirit also conforms us to the image of Jesus, which is expressed through outwardly visible actions and attitudes - "But the fruit of the Spirit is love, joy, peace, forbearance, kindness, goodness, faithfulness, gentleness and self-control" (Galatians 5:22-23).