Where is it located about the law and Jesus came because man couldn't obey the law... and what was the law and what is the law today?
It appears that you have mixed up several verses. John 1:17 (ASV) says that “the law was given through Moses; grace and truth came through Jesus Christ.” Romans 8:3-4 (ASV) says that “what the law could not do, in that it was weak through the flesh, God, sending his own Son in the likeness of sinful flesh and for sin, condemned sin in the flesh, that the ordinance of the law might be fulfilled in us, who walk not after the flesh, but after the Spirit.” The law that was set aside was the law of Moses. It was replaced by grace and truth. Both grace and truth are related to law – grace was necessary to provide a sacrifice by which man’s sins could be forgiven and truth (the word of God) instructs us on how to obtain that salvation. In this sense, even grace instructs or teaches us. Titus 2:11-15. The fact that we are under grace does not mean that there is no law. James speaks of the “perfect law of liberty” (James 1:25; 2:12), the “royal law” (James 2:8). Paul refers to the “law of God” (Rom. 7:25), the “law of the Spirit of life in Christ Jesus” (Rom. 8:2), and the “law of Christ” (Gal. 6:2). To be free from the law of Moses is not to be free from all law. If there were no law, there would be no sin (Rom. 4:15; 1 John 3:4), “for sin is the transgression of the law.” As Paul stated in Romans 8:3-4, there was something that the law could not do – it could not bring salvation. Once grace and truth came by Jesus Christ, those who are obedient believers according to the truth will be saved by the grace of God that provided the gift of salvation through Jesus Christ.
For a fuller discussion of the relationship between faith and obedience, see Lesson 5 on James and Jude, James 2:14-26.
You Must Hear the Gospel
Romans 10:17
You must hear the gospel and then understand and recognize that you are lost without Jesus Christ no matter who you are and no matter what your background is. The Bible tells us that “all have sinned, and come short of the glory of God.” (Romans 3:23) Before you can be saved, you must understand that you are lost and that the only way to be saved is by obedience to the gospel of Jesus Christ. (2 Thessalonians 1:8) Jesus said, “I am the way, the truth, and the life: no man cometh unto the Father, but by me.” (John 14:6) “Neither is there salvation in any other: for there is none other name under heaven given among men, whereby we must be saved.” (Acts 4:12) "So then faith cometh by hearing, and hearing by the word of God." (Romans 10:17)
You Must Believe
Hebrews 11:6
You must believe and have faith in God because “without faith it is impossible to please him: for he that cometh to God must believe that he is, and that he is a rewarder of them that diligently seek him.” (Hebrews 11:6) But neither belief alone nor faith alone is sufficient to save. (James 2:19; James 2:24; Matthew 7:21)
You Must Repent
Acts 3:19
You must repent of your sins. (Acts 3:19) But repentance alone is not enough. The so-called “Sinner’s Prayer” that you hear so much about today from denominational preachers does not appear anywhere in the Bible. Indeed, nowhere in the Bible was anyone ever told to pray the “Sinner’s Prayer” to be saved. By contrast, there are numerous examples showing that prayer alone does not save. Saul, for example, prayed following his meeting with Jesus on the road to Damascus (Acts 9:11), but Saul was still in his sins when Ananias met him three days later (Acts 22:16). Cornelius prayed to God always, and yet there was something else he needed to do to be saved (Acts 10:2, 6, 33, 48). If prayer alone did not save Saul or Cornelius, prayer alone will not save you. You must obey the gospel. (2 Thess. 1:8)
You Must Confess
Romans 10:9
You must confess that Jesus Christ is the Son of God. (Romans 10:9-10) Note that you do NOT need to make Jesus “Lord of your life.” Why? Because Jesus is already Lord of your life whether or not you have obeyed his gospel. Indeed, we obey him, not to make him Lord, but because he already is Lord. (Acts 2:36) Also, no one in the Bible was ever told to just “accept Jesus as your personal savior.” We must confess that Jesus is the Son of God, but, as with faith and repentance, confession alone does not save. (Matthew 7:21)
You Must Be Baptized
Acts 2:38
Having believed, repented, and confessed that Jesus is the Son of God, you must be baptized for the remission of your sins. (Acts 2:38) It is at this point (and not before) that your sins are forgiven. (Acts 22:16) It is impossible to proclaim the gospel of Jesus Christ without teaching the absolute necessity of baptism for salvation. (Acts 8:35-36; Romans 6:3-4; 1 Peter 3:21) Anyone who responds to the question in Acts 2:37 with an answer that contradicts Acts 2:38 is NOT proclaiming the gospel of Jesus Christ!
You Must Be Faithful Unto Death
Revelation 2:10
Once you are saved, God adds you to his church and writes your name in the Book of Life. (Acts 2:47; Philippians 4:3) To continue in God’s grace, you must continue to serve God faithfully until death. Unless they remain faithful, those who are in God’s grace will fall from grace, and those whose names are in the Book of Life will have their names blotted out of that book. (Revelation 2:10; Revelation 3:5; Galatians 5:4)