Matthew 9 (KJV)
(16) No man putteth a piece of new cloth unto an old garment, for that which is put in to fill it up taketh from the garment, and the rent is made worse.
(17) Neither do men put new wine into old bottles: else the bottles break, and the wine runneth out, and the bottles perish: but they put new wine into new bottles, and both are preserved.
Vss. 16 & 17 make the same point: Speaking of religious conventions, adding the new to the old will not make the old better, but make them both useless. The new covenant of grace cannot successfully be added to the old covenant of law.
In John 12:24 (KJV) Jesus said,
(24) Verily, verily, I say unto you, Except a corn of wheat fall into the ground and die, it abideth alone: but if it die, it bringeth forth much fruit.
Jesus spoke of His own death, but not only that. As God's sacrificial Lamb, Jesus was condemned to die according to the law, bearing all of the world's sin-guilt(John 1:29), that the law would be perfectly fulfilled. In Jesus, God judged the world's sin, ending the law's jurisdiction.
Romans 3:19-26 (KJV)
(19) Now we know that what things soever the law saith, it saith to them who are under the law: that every mouth may be stopped, and all the world may become guilty before God.
(20) Therefore by the deeds of the law there shall no flesh be justified in his sight: for by the law is the knowledge of sin.
(21) But now the righteousness of God without the law is manifested, being witnessed by the law and the prophets;
(22) Even the righteousness of God which is by faith of Jesus Christ unto all and upon all them that believe: for there is no difference:
(23) For all have sinned, and come short of the glory of God;
(24) Being justified freely by his grace through the redemption that is in Christ Jesus:
(25) Whom God hath set forth to be a propitiation through faith in his blood, to declare his righteousness for the remission of sins that are past, through the forbearance of God;
(26) To declare, I say, at this time his righteousness: that he might be just, and the justifier of him which believeth in Jesus.
Jesus established a new covenant, with a new law of far greater depth and breadth than the old law:
John 13:34-35 (KJV)
(34) A new commandment I give unto you, That ye love one another; as I have loved you, that ye also love one another.
(35) By this shall all men know that ye are my disciples, if ye have love one to another.
In view of vs. 34b, obeying Jesus' new commandment by our own will and strength is impossible. Only Jesus, or someone yielded to His Holy Spirit, could do that. Even following the Ten Commandments is impossible in our own strength. Hebrews 4:12-13 mandates not only their actions and restrictions, but the godly attitudes behind them as well.
Hebrews 4:12-13 (KJV)
(12) For the word of God is quick, and powerful, and sharper than any twoedged sword, piercing even to the dividing asunder of soul and spirit, and of the joints and marrow, and is a discerner of the thoughts and intents of the heart.
(13) Neither is there any creature that is not manifest in his sight: but all things are naked and opened unto the eyes of him with whom we have to do.
Apostle Paul thoroughly covered the law in relation to the new covenant of grace:
Colossians 2:8-23 (KJV)
(8) Beware lest any man spoil you through philosophy and vain deceit, after the tradition of men, after the rudiments of the world, and not after Christ.
(9) For in him dwelleth all the fulness of the Godhead bodily.
(10) And ye are complete in him, which is the head of all principality and power:
(11) In whom also ye are circumcised with the circumcision made without hands, in putting off the body of the sins of the flesh by the circumcision of Christ:
(12) Buried with him in baptism, wherein also ye are risen with him through the faith of the operation of God, who hath raised him from the dead.
(13) And you, being dead in your sins and the uncircumcision of your flesh, hath he quickened together with him, having forgiven you all trespasses;
(14) Blotting out the handwriting of ordinances that was against us, which was contrary to us, and took it out of the way, nailing it to his cross;
(15) And having spoiled principalities and powers, he made a shew of them openly, triumphing over them in it.
(16) Let no man therefore judge you in meat, or in drink, or in respect of an holyday, or of the new moon, or of the sabbath days:
(17) Which are a shadow of things to come; but the body is of Christ.
(18) Let no man beguile you of your reward in a voluntary humility and worshipping of angels, intruding into those things which he hath not seen, vainly puffed up by his fleshly mind,
(19) And not holding the Head, from which all the body by joints and bands having nourishment ministered, and knit together, increaseth with the increase of God.
(20) Wherefore if ye be dead with Christ from the rudiments of the world, why, as though living in the world, are ye subject to ordinances,
(21) (Touch not; taste not; handle not;
(22) Which all are to perish with the using;) after the commandments and doctrines of men?
(23) Which things have indeed a shew of wisdom in will worship, and humility, and neglecting of the body; not in any honour to the satisfying of the flesh.
Just as the old garment of Matthew 9:16 and the old wineskin of Matthew 9:17 are useless when filled with the new, so the old covenant laws are useless, and even a hindrance, in the new covenant of grace.
(If you made it this far, you probably noticed my use of the King James Version throughout. That is to accommodate our more legalistic brethren, who seem to lend more authority to the KJV than the more contemporary versions. As this study contrasts the new covenant of the spirit and love with the old covenant of the word and judgment, I thought any accommodation to the weaker brethren might help them accept the truth more easily.)