Works do not save us. If they did Immanuel would not have had to die on the cross as that final blood sacrifice for all sins and as the unblemished lamb. Good works are a sign of our salvation. Not a means to achieve our salvation.
God's grace saves. That alone is his irrevocable calling and gift to us. All we need to receive it? Faith in Christ and his message on the cross. The moment we believe we are indwelt by the holy spirit that knew us before the creation of the world. Because Jesus / Immanuel knows his sheep by name. And we know him.
Many are called but few are chosen. Many claim Christ but few are the chosen, the elect, of God. We see this when we witness celebrities wearing diamond encrusted crosses and yet acting like the devil.
John 10:27-28 My sheep hear my voice, and I know them, and they follow me: And I give unto them eternal life; and they shall never perish, neither shall any man pluck them out of my hand