Try to understand what these scriptures are saying to those that are under the law.
Rom 3:19-22 ~ 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. 20Therefore by the deeds of the law there shall no flesh be justified in his sight: for by the law is the knowledge of sin. 21But now the righteousness of God without the law is manifested, being witnessed by the law and the prophets; 22Even the righteousness of God which is by faith of Jesus Christ unto all and upon all them that believe: for there is no difference.
1Cor 15:56 ~ The sting of death is sin; and the strength of sin is the law.
Rom 6:14,15 ~ For sin shall not have dominion over you: for ye are not under the law, but under grace. 15What then? shall we sin, because we are not under the law, but under grace? God forbid.
1Cor 9:20,21 ~ And unto the Jews I became as a Jew, that I might gain the Jews; to them that are under the law, as under the law, that I might gain them that are under the law; 21To them that are without law, as without law, (being not without law to God, but under the law to Christ,) that I might gain them that are without law.
Gal 3:21-29 ~ Is the law then against the promises of God? God forbid: for if there had been a law given which could have given life, verily righteousness should have been by the law. 22But the scripture hath concluded all under sin, that the promise by faith of Jesus Christ might be given to them that believe. 23But before faith came, we were kept under the law, shut up unto the faith which should afterwards be revealed. 24Wherefore the law was our schoolmaster to bring us unto Christ, that we might be justified by faith. 25But after that faith is come, we are no longer under a schoolmaster. 26For ye are all the children of God by faith in Christ Jesus. 27For as many of you as have been baptized into Christ have put on Christ. 28There is neither Jew nor Greek, there is neither bond nor free, there is neither male nor female: for ye are all one in Christ Jesus. 29And if ye be Christ's, then are ye Abraham's seed, and heirs according to the promise.
Abraham's seed was according to the promise and not according to the law. The law came 430 years after the promise was given / Gal 3:16,17. Abraham believed the promise by faith and it was put on his account as righteousness. We are the children of God, and heirs according to the promise by faith and not by the works of the law.
Rom 4:13-16 ~ For the promise, that he should be the heir of the world, was not to Abraham, or to his seed, through the law, but through the righteousness of faith. 14For if they which are of the law be heirs, faith is made void, and the promise made of none effect: 15Because the law worketh wrath: for where no law is, there is no transgression. 16Therefore it is of faith, that it might be by grace; to the end the promise might be sure to all the seed; not to that only which is of the law, but to that also which is of the faith of Abraham; who is the father of us all.
Being under the law means, if you transgress or offend the law in any point you have broken the whole law and you are a transgressor of the law. There is no grace or mercy for those who are under the law and transgress. You must be treated as a transgressor and come under the wrath of God because the law worketh wrath / Rom 4:15.
James 2:8-12 If ye fulfil the royal law according to the scripture, Thou shalt love thy neighbour as thyself, ye do well: 9But if ye have respect to persons, ye commit sin, and are convinced of the law as transgressors. 10For whosoever shall keep the whole law, and yet offend in one point, he is guilty of all. 11For he that said, Do not commit adultery, said also, Do not kill. Now if thou commit no adultery, yet if thou kill, thou art become a transgressor of the law. 12So speak ye, and so do, as they that shall be judged by the law of liberty.13For he shall have judgment without mercy, that hath shewed no mercy; and mercy rejoiceth against judgment.
If you live under the law you shall be judged by the law as transgressors, but if you live under grace you shall be judged by the law of liberty where mercy rejoices against judgment. God will never give grace to those that live under the law, therefore, you can't live by grace being under the law. The only righteousness that God will put on our account is when we exercise faith in the promises of God / Rom 1:17. When we mix faith with the promises of God (that came by faith) that will produce works of faith that justifies the fruit of our labor. In that sense we are justified not only by faith but also by works and the fruit of our labor / James 2:21-24. Remember that the first work of God produced in our life was to believe on the name of the Son of God whom God sent/ John 6:29.