Therefore it is of faith that it might be according to grace, so that the promise might be sure to all the seed, not only to those who are of the law, but also to those who are of the faith of Abraham, who is the father of us all (as it is written, "I have made you a father of many nations") in the presence of Him whom he believed, even God, who gives life to the dead and calls those things which do not exist as though they did.  Romans 4:16-17

We can have great certainty concerning the fulfillment of God's promises, because grace and true faith are the foundation of our assurance. "Therefore it is of faith that it might be according to grace, so that the promise might be sure to all the seed." Grace is the heavenly resource behind all of God's promises. Faith is the simple means of accessing that grace. These realities make God's promises certain to all who believe them, whether Jew ("not only to those who are of the law") or Gentile ("but also to those who are of the faith of Abraham"). This is how Abraham related to God's promises. Thereby, he became the spiritual leader for all who would follow his example: "who is the father of us all (as it is written, 'I have made you a father of many nations') in the presence of Him whom he believed."

The true and living God, whom Abraham believed, is a God "who gives life to the dead." Consider the impact this attribute has on our confidence in God's promises. Often, the promises of God must overcome death (or deadening circumstances) in order to be fulfilled. The promise that Lazarus would live again was given while his dead body was lying in a tomb. "He who believes in Me, though he may die, he shall live" (John 11:25). Often, the deadness of our own circumstances wants to challenge the certitude of God's promises. Yet, the God who has made a multitude of promises to us is the God "who gives life to the dead."

The God of promises "calls those things which do not exist as though they did." Yes, we are not yet personally righteous (in any intrinsic sense). Yet, God calls us righteous, justified, and saints in Christ. "Whom He called, these He also justified" (Romans 8:30a). We are not yet glorified (experientially). Yet, God speaks of our glorification as already accomplished. "Whom He justified, these He also glorified" (Romans 8:30b). What a joy to know that our God of promises will bring to pass that which He promises according to His grace. We do not look at the things which are seen, but at the things which are not seen. For the things which are seen are temporary, but the things which are not seen are eternal. 2 Corinthians 4:18 (NKJV)