Notes on the Pentateuch by Mackintosh
Genesis 21:1-34
And the Lord visited Sarah, as he had said, and the Lord did unto Sarah as he had spoken." Here we have accomplished promise the blessed fruit of patient waiting upon God. None ever waited in vain. The soul, that takes hold of God's promise by faith, has gotten a stable reality which will never fail him. Thus was it with Abraham; thus was it with all the faithful from age to age; and thus will it be with all those, who are enabled, in any measure, to trust in the living God. Oh! it is a wonderful blessing to have God Himself as our portion and resting-place, amid the unsatisfying shadows of this scene through which we are passing; to have our anchor cast within the veil; to have the word and oath of God, the two immutable things, to lean upon, for the comfort and tranquility of our souls.
When God's promise stood before the soul of Abraham, as an accomplished fact, he might well have learnt the futility of his own effort to reach that accomplishment. Ishmael was of no use, whatever, so far as God's promise was concerned. He might, and did, afford something for nature's affections to entwine themselves around, thus furnishing a more difficult task for Abraham to perform afterwards; but he was in no wise conducive to the development of the purpose of God, or to the establishment of Abraham's faith quite the reverse. Nature can never do ought for God. The Lord must visit and the Lord must "do," and faith must wait, and nature must be still; yea, must be entirely set aside as a dead, worthless thing, and then the divine glory can shine out, and faith find in that outshining all its rich and sweet reward. "Sarah conceived and bare Abraham a son in his old age, at the set time of which God had spoken to him." There is such a thing as God's "set time," His "due season," and for this the faithful must be content to wait. The time may seem long, and hope deferred may make the heart sick; but the spiritual mind will ever find its relief in the assurance, that all is for the ultimate display of God's glory. "For the vision is for an appointed time, but at the end it shall speak, and not lie; though it tarry, wait for it; because it will surely come, it will not tarry...... but the just shall live by his faith." (Habakkuk 2:3-4) This wondrous faith! It brings into our present all the power of God's future, and feeds upon God's promise as a present reality. By its power the soul is kept hanging upon God, when every outward thing seems to be against it; and, "at the set time," the mouth is filled with laughter. "Abraham was an hundred years old when his son Isaac was born unto him." Thus nature had nothing to glory in. "Man's extremity was God's opportunity;" and Sarah said, "God hath made me to laugh." All is triumph when God is allowed to show Himself.
Now while the birth of Isaac filled Sarah's mouth with laughter, it introduced an entirely new element into Abraham's house. The son of the free-woman very speedily developed the true character of the son of the bond-woman. Indeed, Isaac proved, in principle, to be to the household of Abraham, what the implantation of the new nature is in the soul of a sinner. It was not Ishmael changed, but it was Isaac born. The son of the bond-woman could never be anything else but that. He might become a great nation, he might dwell in the wilderness, and become an archer, he might become the father of twelve princes, but he was the son of the bond-woman all the while. On the contrary, no matter how weak and despised Isaac might be, he was the son of the free-woman. His position and character, his standing and prospects, were all from the Lord. "That which is born of the flesh is flesh; and that which is born of the Spirit is spirit."
Regeneration is not a change of the old nature, but the introduction of a new; it is the implantation of the nature or life of the Second Adam, by the operation of the Holy Ghost, founded upon the accomplished redemption of Christ, and in full keeping with the sovereign will or counsel of God. The moment a sinner believes in his heart, and confesses with his mouth, the Lord Jesus, he becomes the possessor of a new life, and that life is Christ. He is born of God, is a child of God, is a son of the free-woman. (See Romans 10:9; Colossians 3:4; 1 John 3:1-2; Galatians 3:26; Galatians 4:31)
Nor does the introduction of this new nature alter, in the slightest degree, the true, essential character of the old. This latter continues what it was, and is made, in no respect, better; yea, rather, there is the full display of its evil character in opposition to the new element. "The flesh lusteth against the Spirit, and the Spirit against the flesh; and these are contrary the one to the other." There they are in all their distinctness, and the one is only thrown into relief by the other.
I believe this doctrine of the two natures in the believer is not generally understood; and yet, so long as there is ignorance of it, the mind must be utterly at sea, in reference to the true standing and privileges of the child of God. Some there are, who think that regeneration is a certain change which the old nature undergoes; and, moreover, that this change is gradual in its operation, until, at length, the whole man becomes transformed. That this idea is unsound, can be proved by various quotations from the New Testament. For example, "the carnal mind is enmity against God." How can that, which is thus spoken of, ever undergo any improvement? The apostle goes on to say, "it is not subject to the law of God, neither indeed can be." If it cannot be subject to the law of God, how can it be improved How can it undergo any change? Again, "that which is born of the flesh is flesh." Do what you Will with flesh, and it is flesh all the while. As Solomon says, "Though thou shouldest bray a fool in a mortar, among wheat with a pestle, yet will not his foolishness depart from him." (Proverbs 27:22) There is no use in seeking to make foolishness wise: you must introduce heavenly wisdom into the heart that has been heretofore only governed by folly. Again, "ye have put off the old man." (Colossians 3:9) He does not say, Ye have improved, or are seeking to improve, "the old man;" but, Ye have put it off. This gives us a totally different idea. There is a very great difference between seeking to mend an old garment, and casting it aside altogether, and putting on a new one. This is the ides of the last-quoted passage. It is a putting off the old, and a putting on of the new. Nothing can be more distinct or simple.
Passages might easily be multiplied to prove the unsoundness; of the theory, with respect to the gradual improvement of the old nature to prove that the old nature is dead in sins, and utterly unrenewable and unimproveable; and, moreover, that the only thing we can do with it is, to keep it under our feet in the power of that new life, which we have in union with our risen Head in the heavens.
The birth of Isaac did not improve Ishmael, but only brought out his real opposition to the child of promise. He might have gone on very quietly and orderly till Isaac made his appearance; but then he showed what he was, by persecuting and mocking at the child of resurrection. What then was the remedy? To make Ishmael better? By no means; but, "cast out this bondwomen and her son; for the son of this bond-woman shall not be heir with my son, even with Isaac." (8-10) Here was the only remedy. "That which is crooked cannot be made straight;" therefore you have only to get rid of the crooked thing altogether, and occupy yourself with that which is divinely straight. It is labour lost to seek to make a crooked thing straight. Hence all efforts after the improvement of nature, are utterly futile, so far as God is concerned. It may be all very well for men to cultivate and improve that which is of use to themselves; but God has given his children something infinitely better to do, even to cultivate that which is His own creation, the fruits of which, while they, in no wise, serve to exalt nature, are entirely to His praise and glory.
Now the error into which the Galatian churches fell, was the introduction of that which addressed itself to nature. "Except ye be circumcised after the manner of Moses, ye cannot be saved." Here salvation was made to depend upon something that man could be, or man could do, or man could keep. This was upsetting the whole glorious fabric of redemption, which, as the believer knows, rests exclusively upon what Christ is, and what He has done. To make salvation dependent, in the most remote manner, upon anything in, or done by, man, is to set it entirely aside. In other words, Ishmael must be entirely cast out, and all Abraham's hopes be made to depend upon what God had done, and given, in the person of Isaac. This, it is needless to say, leaves man nothing to glory in. If present or future blessedness were made to depend upon even a divine change wrought in nature, flesh might glory. Though my nature were improved, it would be something of
me, and thus God would not have all the glory. But when I am introduced into a new creation, I find it is all of God, designed, matured, developed by Himself alone. God is the actor, and I am a worshipper; He is the blesser, and I am the blessed; He is "the better," and I am "the less;" (Hebrews 7:7) He is the giver, and I am the receiver. This is what makes Christianity what it is; and, moreover, distinguishes it from every system of human religion under the sun, whether it be Romanian, Puseyism, or any other ism whatsoever. Human religion gives the creature a place more or less; it keeps the bond-woman and her son in the house; it gives man something to glory in. On the contrary, Christianity excludes the creature from all interference in the work of salvation; casts out the bond-woman and her son, and gives all the glory to Him, to whom alone it is due.
But let us inquire who this bond-woman and her son really are, and what they shadow forth. Galatians 4:1-31 furnishes ample teaching as to these two points. In a word, then, the bond-woman represents the covenant of the law; and her son represents all, who are "of works of law," or on that principle ( ex ergon nomou). This is very plain. The bond-woman only genders to bondage, and can never bring forth a free man. How can she? The law never could give liberty, for so long as a man was alive it ruled him. (Romans 7:1) I can never be free so long as I am under the dominion of any one. But while I live, the law rules me; and nothing but death can give me deliverance from its dominion. This is the blessed doctrine of Romans 7:1-25. "Wherefore, my brethren, ye also are become dead to the law by the body of Christ, that you should be married to another, even to him that is raised from the dead, that we should bring forth fruit unto God." This is freedom; for, "If the Son shall make you free, ye shall be free indeed.'' (John 8:36) So, then, brethren, we are not children of the bond-woman, but of the free." (Galatians 4:31)
Now, it is in the power of this freedom that we are enabled to obey the command, cast out this bondwoman and her son." If I am not consciously free, I shall be seeking to attain liberty in the strangest way possible, even by keeping the bond-woman in the house: in other words, I shall be seeking to get life by keeping the law; I shall be establishing my own righteousness. No doubt, it will involve a struggle to cast out this element of bondage, for legalism is natural to our hearts. "The thing was very grievous in Abraham's sight, because of his son." Still, however grievous it may be, it is according to the divine mind that we should abidingly stand fast in the liberty wherewith Christ hat made us free, and not be entangled again with the yoke of bondage." (Galatians 5:1) May we, beloved reader, so fully and experimentally enter into the blessedness of God's provision for us in Christ, that we may be done with all thoughts about the flesh, and all that it can be, do, or produce. There is a fullness in Christ which renders all appeal to nature utterly superfluous and vain.