Keeping the law for salvation
First let’s establish whether the Law spoken with its 613 commands is the Mosiac law. Any Bible reader who understand the old covenant knows the law is not just the 10 commandments that were first given to Moses on mount Sinai.
Israel was told to obey all the commandments to be blessed not just 10.
In the New Testament we read of the church working out the Gentiles now entering the church that were in the beginning Jews.
“Wherefore my sentence is, that we trouble not them, which from among the Gentiles are turned to God: But that we write unto them, that they abstain from pollutions of idols, and [from] fornication, and [from] things strangled, and [from] blood. For Moses of old time hath in every city them that preach him, being read in the synagogues every sabbath day.” (Acts 15:19-21)
(In other words, those requirements were not for salvation, but to keep from offending the Jews that still clung to elements of the Mosaic Law as they transitioned into the New Covenant.)
"Since we have heard that some who went out from us have troubled you with words, unsettling your souls, saying, “You must be circumcised and keep the law” —to whom we gave no such commandment— it seemed good to us, being assembled with one accord, to send chosen men to you with our beloved Barnabas and Paul, men who have risked their lives for the name of our Lord Jesus Christ. We have therefore sent Judas and Silas, who will also report the same things by word of mouth. For it seemed good to the Holy Spirit, and to us, to lay upon you no greater burden than these necessary things: 29 that you abstain from things offered to idols, from blood, from things strangled, and from sexual immorality. If you keep yourselves from these, you will do well.” (Acts 15:24-29 NKJV)
(This is a direct statement for the Early Church by the apostles did not require Christians to keep the Mosaic Law.)
Paul explained for himself “For though I am free with respect to all, I have made myself a slave to all, so that I might win more of them. To the Jews I became as a Jew, in order to win Jews. To those under the law I became as one under the law (though I myself am not under the law) so that I might win those under the law. To those outside the law I became as one outside the law (though I am not free from God’s law but am under Christ’s law) so that I might win those outside the law. To the weak I became weak, so that I might win the weak. I have become all things to all people, that I might by all means save some. I do it all for the sake of the gospel, so that I may share in its blessings.” (1 Corinthians 9:19-23 NRSV and other translations)
Christ did not come to do half of the job, but a full work. The Law was a schoolmaster to lead us to Christ. Christ fulfilled it and nailed the “handwriting of ordinances against us” to His cross. The law was against us. His finished work set us free from the “law of sin and death” (Mosaic Law) by giving us His Spirit of Life.
The law was our schoolmaster to bring us to Christ, that we might be justified by faith. But after that faith is come, we are no longer under a schoolmaster. Ga 3:24-25
Faith in Christ separates one from the law, the schoolmaster and we are under Christ, and we follow Christ who is the fulfiller of the law.
Mat 5:20 “because I tell you, unless your righteousness greatly exceeds that of the scribes and Pharisees, you will never enter the kingdom from heaven!”
How can our righteous exceed those who whole life revolved around the Bible and the laws? Its not by our own righteousness, our works (which the Pharisees were depending on). By Christ who is our righteousness. It is by our putting on Christ, walking in the Spirit who changes us to be like Jesus daily, that is what we are to focus on.
"If there had been a law which could have given life, verily righteousness would have been by the law" (Galatians 3:21).
Instead God gave his only Son.