"For we have come to share in Christ, if indeed we hold our original confidence firm to the end." Whether you believe that Christians who are once saved are always saved or if you believe that Christians can fall away, the sober warning in this passage should be taken seriously by Christians of both views. Being a Christian means you have resolved to be faithful to God no matter what happens in your life---it is a lifetime resolution. When a Christian experiences the ups and downs of life and remains faithful to God, it builds a confidence and assurance that one does, in fact, share in the eternal life of Christ. Because being a Christian doesn't always come easy, this verse provides a grave warning to everyone who claims to be saved to examine yourself carefully to be sure that you have the fortitude and resolve to persevere in your faith in Christ. Never mind trying to figure out who is a true believer and who is not; build up your own endurance because you belong to Christ if you hold fast your confidence to the end (vs. 5, 14).
