Abraham had already lived a hundred years, and he had the better half of the next century to continue growing in faith. God had made plain that the salvation he had in store for his people would be accomplished not by some prescribed activities and works of man, but by God himself. He had been shown that all of salvation must be received by faith. Faith is the living bond the links us to Christ. Through that bond all the benefits of Christ’s work are imputed unto us. Through that bond flows all the spiritual life that fills our heart. But what about that faith itself? Is there something here that man can do? Is faith the part that God has left for man to accomplish by his will, strength, and mental activity? Does faith mean that Abraham must find a clever way to fulfill the promise of a son when obstacles such as a barren wife are thrown into the way? Abraham listened to the argument of his wife and concluded that he must do his part and use Hagar to obtain this son. Ishmael was now about twelve years old, and Abraham seemed to have convinced himself that Ishmael was the son whom God had promised.
But it was just when Abraham began to find peace and rest in his own imaginations—when it was “obvious” that Sarah would not be the mother of the promised child—that God appeared to him, renewed the same covenant promise established earlier, and revealed that the promised child would indeed be born from Sarah. God himself would see to it that his promise would be fulfilled. God had promised a son, and Abraham knew by faith that God would fulfill his promise, but it was not for Abraham to use worldly wisdom to guarantee that this promise would be fulfilled. Faith has no room for some conditional part accomplished by man. True, faith is active and living, and becomes evident in the fruits of godly living (James). The godly living and good works are not parts of faith, but rather the fruit of faith. There really is nothing left for man to do. The only thing the child of God can do is respond in wonder, amazement, and even in astounded laughter (Genesis 17:17).
The name Isaac means “laughter,” and would remind Abraham and Sarah for the rest of their lives of the wonder of God’s salvation. It is in the nature of man to think that he must do something to atone for his sin or give God reason for saving him. Rather, salvation is ALL of God. God uses Paul to spell out this truth in Romans 9:7–10: “Neither, because they are the seed of Abraham, are they all children: but, In Isaac shall thy seed be called. That is, They which are the children of the flesh, these are not the children of God: but the children of the promise are counted for the seed. For this is the word of promise, At this time will I come, and Sarah shall have a son.” And in his letter to the Corinthians he writes “For the preaching of the cross is to them that perish foolishness; but unto us which are saved it is the power of God. For it is written, I will destroy the wisdom of the wise, and will bring to nothing the understanding of the prudent. … But unto them which are called, both Jews and Greeks, Christ the power of God, and the wisdom of God. Because the foolishness of God is wiser than men; and the weakness of God is stronger than men. For ye see your calling, brethren, how that not many wise men after the flesh, not many mighty, not many noble, are called: But God hath chosen the foolish things of the world to confound the wise; and God hath chosen the weak things of the world to confound the things which are mighty; And base things of the world, and things which are despised, hath God chosen, yea, and things which are not, to bring to nought things that are: That no flesh should glory in his presence.”
(1Cor. 1:18–19, 24–29) In contrast to the truth revealed by God, every heresy to one degree or another gives glory to man, which is due to God alone.
The church at this point in history has learned much about the salvation God has in store for man. So if this salvation that God has in store for is something that God accomplishes without help or payment from man, and even the bond of faith through which the blessings of salvation are imputed unto man is not dependent upon any activity of man, how is it determined who are saved and who are not? From where does this faith come? Since faith is not something that comes from the power of our own flesh and will, perhaps it is something that comes from being born to the right parents. That is not the case either. God makes clear that faith itself and the salvation received through faith have nothing to do with our flesh, but everything is according to the sovereign good pleasure of God himself. From this child, Isaac, who was given in fulfillment of God’s promise and not in fulfillment of any conditions or natural ability of man, another wonder is revealed. To Isaac are born twin sons, in whom God reveals that he sovereignly chooses one and reprobates the other. Paul writes in Romans 9:10–11: “And not only this; but when Rebecca also had conceived by one, even by our father Isaac; (For the children being not yet born, neither having done any good or evil, that the purpose of God according to election might stand, not of works, but of him that calleth;).”
Opponents of the truth that God reveals here—unconditional salvation on the basis of God’s will, to elect some and reprobate others, and accomplished by sovereign grace through Christ alone—imagine that such theology makes man a mere stock and block. They argue that it depletes man of his humanity. If natural man has no freedom to choose and accept God’s well-meant offer of salvation, then he loses an essential part of what makes him human. They further argue that a doctrine of total depravity and sovereign reprobation turns a man into an obnoxious beast. To such men God replies, “Who art thou that repliest against God?” (Rom. 9:20). The child of God does not need a shred of his own dignity, but rejoices only in the goodness of God and the dignity he has in Christ alone. The reality is that the life of a child of God is most active and filled with the drama of battle, and total depravity and sovereign reprobation are evident among some of the most attractive people found in the world.
In contrast to this proud assessment of God and man, we see in the life of Isaac what real human life as a child of God is. His own name reminded him that the ways and thinking of man are not the ways and thinking of God. His two children, Jacob and Essau, were constant reminders of God’s sovereign choice even before they were born. The spiritual life of Jacob grew throughout his life, and the spiritual death in Esau was made more and more evident in his life. But this does not mean that Isaac lived like a robot under God’s control. Sovereign election makes us righteous before God in Christ, but the old man of sin cleaves to us in this life, and our battles serve to open our eyes more and more to the depths of God’s love and his holiness. The truths of sovereign grace take nothing from real human life and direct all the glory and honor to God alone.
The life of Isaac illustrates the battle against the old man of sin and pride that clings to us, and it demonstrates the peace, joy, and rest that we have in Christ alone. His life is the reality of life for the child of God in contrast to the imaginary life of mustering up a will to accept Christ and living in fear that we are not doing enough to merit God’s favor and are in danger of falling away from grace. Even though Isaac did not see any spiritual fruit in the life of Esau, the natural attraction of his flesh to the earthly interests and activity of Esau pulled him into a worldly way of thinking so that Esau became his favorite, and he “loved him because he did eat of his venison” (Gen. 25:28). The old man of sin living within Isaac and Rebecca introduced conflict into the home, which grew between the boys as well, as is evident when Esau sold his birthright and Jacob relied on his patience and craftiness. Isaac again fell into the same foolish trap of fear and lied to Abimelech concerning his wife. Even so, the new life of Christ persisted, and God blessed Isaac (Gen. 26:12), and so increased his wealth that the enemies of God around him could do nothing but confess that Jehovah God was with him. God drew Isaac to himself in covenant love and again spoke to him the comforting words of the covenant (Gen. 26:24).
Gradually the eyes of Isaac were opened to the spiritual corruption in his son as he experienced grief in Esau’s marriage to an unbelieving wife (Gen. 26:35). The battles for the elect children of God are long, painful, and exhausting, to the point that Rebecca complained she was “weary of life” (Gen. 27:46). One would think that those who are regenerated and born “after the Spirit” would be filled with pleasant personality traits and enjoyable company, but often that is not the case. Jacob did not seem to possess many qualities attractive to the flesh, and neither did most of the Israelites later on. In contrast, one would think that the wickedness and pride of an unbelieving reprobate would be evident in obnoxious personality traits, but often the most attractive people are the heretics and unbelievers. As with Isaac, we too are often fooled by the earthly attractions we find in this life, and we suffer the consequences. By the grace of God alone, our eyes are opened and we grow in grace. We see more and more the wonder of God’s love for unworthy sinners, and we learn more and more the blessedness of giving all the glory to God alone.