From the outset of His ministry our Lord was careful to affirm that He came not to dissolve but to make good divine authority in the law or the prophets. In both He was predicted as the One on whom all blessing depended. He only could deliver sinful and seduced man. He was to be the sacrifice which would justify all previous offerings to God, and render their just interpretation, and furnish their efficacy. Fulfillment of a prophecy is the same word; but the context here points to a larger scope.
The law and the prophets testified to man's, unrighteousness and to God's righteousness (Rom. 3:21). But they could not do more. Christ came, not to enfeeble or undo them as His blind enemies thought, but to make good that divine testimony which left the sinner without excuse and gave what God only in His grace could supply. It was far more than even pious men conceived, a mere making up, by His obedience of the law, what men failed in. This had merely been man's righteousness accomplished by Him for the unrighteous. Here too He has done incomparably more and better. He laid the basis in His obedience unto death. for God's righteousness, that God might be just and justify him that believes on Jesus. For He who knew no sin glorified God in being made sin for us, that we might become God's righteousness in Him. Hence God's grace is enhanced, not frustrated; for if righteousness is through law, then Christ died gratuitously. But it is not so: never was anything else contemplated or revealed but that the believers rest their hope on His death.
God took care therefore that promise should long precede and exist independently of it, as the apostle argues in Gal. 3 This at Sinai Israel in their self-confidence overlooked. Instead of asking for the unconditional promise of grace they undertook to stand on their own obedience. As no sinful man can subsist on such a condition, the law written on stones, even when brought down a second time with types of mercy accompanying, could not but be a ministry of death and condemnation (2 Cor. 3:7-9). For them it is said in the reading of the old covenant the veil remains unremoved; and the veil is more than on the face, being upon their heart. They did and do not look to Christ, law's end for righteousness to everyone that believes. They strove to stand on a mixture of law and grace, which only adds to the sinner's condemnation, because the added grace increases his guilt if disobedient. But we look on the glory of the Lord with unveiled face and are transformed to the same image from glory to glory, even as by the Lord the Spirit, Who testifies to Him in the glory of God as the fruit not only of His person but of His work. And so the apostle preached the gospel of God's grace and of Christ's glory, as he had been converted.
The Epistle to the Hebrews told the Christian Jews that the " new" covenant of which Jeremiah bore witness held out under Christ a better covenant. It did not, like the old at Sinai, depend on Israel as the party on whose fidelity blessing depended. All hung for the new covenant on the Lord's sovereign grace. " Because this is the covenant that I will covenant for the house of Israel after those days, saith the Lord: giving my laws into their mind, I will also inscribe them on their hearts; and I will be to them for God, and they shall be to me for people. And they shall in no wise teach, each his fellow-citizen and each his brother, saying, Know the Lord; because all shall consciously know from little of them unto great of them; because I will be merciful to their unrighteousnesses and their sins, and their lawlessnesses I will remember no more " (Heb. 8:10-12).
This was no real way to set aside the law and the prophets, but to fulfill them to God's glory and for man's salvation and blessing. Christ filled up the gap between God and the sinner for him who believes on Him. The law pointed to Him as the coming One who alone could restore the balance which the creature's evil had disturbed by weight overwhelming to all but the Savior. He alone could by redemption win and give the blessing which God's nature loved to bestow and God's counsels assured in due time. But all this and more Christ was by His word and Spirit bringing in a new and divine life by faith into the soul, before the day arrives when He will transform our body of humiliation into conformity with His body of glory according to the working of His power even to subdue all things to Himself. It was not mere addition, as if the law and the prophets were not intrinsically complete and perfect for the end God proposed; but He is throughout assumed and predicted as essential to give the blessed result. " For verily I say to you, Till the heaven and the earth pass, one iota or one tittle shall in no wise pass from the law till all come to pass " (vers. 18).
So even the N. T. speaks of filling up the gap otherwise left in it by the revelation of the mystery of Christ's headship on high and the church united to Him as His body. And the apostle in Col. 1:25 tells us of the stewardship of God given Him thereby to complete His word. For this was a secret hidden from ages and generations, and quite distinct from the kingdom, the new covenant, or the inheritance of Abraham's promise. It was a promise in Christ Jesus through the gospel and God's eternal purpose which He purposed in Christ Jesus our Lord (Eph. 3:6, 10).
O dear reader, look you by faith to Jesus, the sole accomplisher of what you most want and of infinitely more-what glorifies God and gives the believer a wondrous part in it all. Look not to yourself save to condemn yourself; look to Him who secures from all condemnation which you must otherwise dread. May your heart learn how truly Christ is all. This no man is willing to do, until he is brought to the decided conviction before God, that he is lost, and that in him (that is, in his flesh) good does not dwell.