What does Hebrews 6:14 mean?

This specific guarantee from God is found in Genesis 22:17. The theme of this passage is confident reliance on the promises of God. Abraham serves as an example of this patient faith. God swore oaths to Abraham on His own name, since there is no one higher God could swear by. Using this human convention, Abraham was reassured that whatever God vowed to do, He really would do.

Abraham did not live to see all of those promises completely fulfilled. And yet, those who came after Abraham saw God's oaths to him come true. Those descendants ought to have even more confidence in God, since they have seen that much more proof of God's nature. In the same way, modern Christians have even more history to support the truth of God's Word than the early church did, and we ought to be comforted as a result.

In the context of this passage, confidence is crucial. Those stuck in spiritual immaturity are still wrestling with doubts and fears about fundamental Christian doctrines. In order to move beyond that shallow grasp of truth—and the danger it represents—it's absolutely necessary to have assurance, confidence, and trust in the promises of God. The writer seems concerned that whatever confidence his readers have, for now, might be wearing thin. For the Jewish Christians of the early church, there would have been no better example of that kind of faith than Abraham.