Actually, both are speaking about the Mosaic law.
Acts 15:5
15:5
But there rose up certain of the sect of the Pharisees which believed, saying, That it was needful to circumcise them, and to command them to keep the law of Moses.
Is not the LAW OF MOSES the Mosaic Law?
Again, I cited Christ's criticism of the Pharisees in Matthew 15:2-9 and Mark 7:6-9 to show that the Pharisees were setting aside the commands of God in order to establish their own traditions and were treating their own teachings as if they were the commands of God, so what they were teaching as the Mosaic Law was actually their own traditions. The is demonstrated by the fact that issue being discussed in Matthew 15 about whether someone could become common by eating with unwashed hands is a tradition of the elders and not something command by the Mosaic Law. This is also demonstrated in Acts 15:1 they were wanting to require Gentiles to become circumcised in order to become saved as part of obeying the Mosaic Law in spite of the fact that that requirement is found nowhere in it.
The issue was that according to Isaiah 45:25, all Israel will be saved, so some Jews mistakenly thought that meant that Gentiles needed to become Jewish proselytes in order to become saved, which meant becoming circumcised and which meant joining the group of people who agreed to do everything that Moses said at Sinai (Exodus 20:19, Deuteronomy 5:22-33). Moses had the authority to interpret the Law, but in Exodus 18, he delegated his authority, and by the first century those who had this authority passed down to them were referred to as sitting in Moses' seat, and their rulings had becoming a large body of oral laws, traditions, and fences, which Jesus referred to as placing a heavy burden on the people (Matthew 23:2-4). So by becoming circumcised, Gentiles were becoming Jewish proselytes and agreeing to live as Jews according to all of their oral laws and traditions, and doing all of this in order to become saved, and this is what the Jerusalem Council rejected, not obedience to our God's commands.
Rom 7:8-11
:8
But sin, taking occasion by the commandment, wrought in me all manner of concupiscence. For without the law sin
was dead.
7:9
For I was alive without the law once: but when the commandment came, sin revived, and I died.
7:10
And the commandment, which
was ordained to life, I found
to be unto death.
7:11
For sin, taking occasion by the commandment, deceived me, and by it slew
me.
The commandment, that would be the 10 Commandments one of which he just quoted, was ordained to life. But he found to be unto death.
Is the law sin, God forbid. We need to remember why the law was given originally.
It is the law of sin that stirred up sin to bear fruit unto death (7:5), that held Paul captive (7:6), that gave sin its power (7:8), that seized the opportunity through the commandment to deceive Paul and slay him (7:11), that caused him not to do the good that he wanted to do (7:13-20), that held him captive (7:23), and that is the law that he served with his flesh (7:25), while it is God's Law that is not sin, but reveals what sin is (7:7), that is holy, righteous, and good (7:12), that is the good that Paul did not blame for bringing death to him (7:13), that is the good that he wanted to do (7:13-20), that is the good that he delighted in doing (7:22), and that is the law that he served with his mind (7:25).
Exodus 19. God wanted to make them a kingdom of priests, but the people exposed there self-righteousness when they said all that God commands us we are able to perform. They were totally incapable of doing what God told them to do. They broke the Sabbath by looking for the Manna on the Sabbath when He told them not to.
They murmured and complained and wanted to go back to Egypt.
So when they exposed there self-righteous pride, God had to expose there sin.
So, He gave them the 10 Commandments.
Saying that "all that God has said we will do" was agreeing to the terms of the covenant and essentially sealing it with an "I do" to God's marriage proposal, so it had absolutely nothing to do with either with their self-righteousness or with God exposing it. God said that what He commanded was not too difficult and I believe Him, and many are able to what He commanded by grace through faith. All throughout the Bible, God wanted His chosen people to repent and turn back to obedience to Him, so God does not turn around and show contempt for people who seek to obey His commands. God's commands were given to reveal our sin, but they were primarily given to teach how to walk in God's ways in accordance with His attributes, and revealing our sins has significance only insofar as it leads us to repent and turn back to obedience. In any case, if you agree that the Law was given to reveal what sin is and you agree that we should not do what God has revealed to be sin, then you should agree that we should obey the Law.
The law was our tutor to bring us to Christ, but now that we are in Christ, we are no longer under the tutor. Galatians 3:24-25
Having no more need for a tutor is not at all the same thing as having no more need to live according to what the tutor taught us. Someone who was to disregard everything that their tutor taught them after they reached the point where they no longer needed a tutor would be completely missing the whole point of a tutor. Christ was sinless, so he set a perfect example of how to walk in obedience to the Mosaic Law, and we are told to follow his example (1 Peter 2:21-22), to walk in the same way he walked (1 John 2:6), and to be imitators of him (1 Corinthians 11:1), so now that he has come, we have a superior teacher, but the subject matter is still how to walk in God's ways in accordance with His attributes. We now also have the Spirit, who has the role of leading us to obey God's Law (Ezekiel 36:26-27).
