I think what you think what they are saying is that salvation is by works.
I also think that anyone would think exactly that if they ignored the context of God's sovereignity and how & why it is greater than the limited freedom of man's will.
Thanks for asking and expecting an answer without bothering to address any of what I said directly because it actually really helps in my character development, as discouraging of my hopes for good conversation it may be.
Salvation has always been by faith.
It helps to lay out what that involves.
Abraham was promised that the world would be blessed through being in his seed.
The Jews took it to mean that those who were followers of Abraham’s beliefs would be the seed, so all those who wanted to be blessed would have to do was to become Jews.
But Paul clarifies that the criteria of who would be considered by God to be a child of Abraham would be faith, not circumcision. God considered Abraham as family even before he accepted circumcision.
Why was law added? To guard Israel, until Christ came and gave the new way of faith, leading to grace. Else they would have gone the way of Sodom and Gomorrah, because of the weakness of the flesh.
How did the Covenant of Law/Works work, bless, serve?
A believer would try to follow the law, fail and beg for mercy. That's why the option of the sin offerings were provided.
However, to make sin offerings, would imply that a believer confessed to being a sinner.
So the Covenant of works would be of no benefit if a Jew substituted the commandments of God for the traditions of men, for evil purposes, to serve Baal:
Mark 7:9-13
9He was also saying to them, “You are experts at setting aside the commandment of God in order to keep your tradition.
10“For Moses said, ‘HONOR YOUR FATHER AND YOUR MOTHER’; and, ‘HE WHO SPEAKS EVIL OF FATHER OR MOTHER, IS TO BE PUT TO DEATH’;
11but you say, ‘If a man says to his father or his mother, whatever I have that would help you is Corban (that is to say, given to God),’
12you no longer permit him to do anything for hisfather or his mother;
13thus invalidating the word of God by your tradition which you have handed down; and you do many things such as that.”
So the Covenant of Works/Law, served, blessed, protected a believer if he was faithful, believed in the commandments of God in their original form and tried to follow them. As seen in the parable of the Publican and the Pharisee:
Luke 18:9-14
9And He also told this parable to some people who trusted in themselves that they were righteous, and viewed others with contempt:
10“Two men went up into the temple to pray, one a Pharisee and the other a tax collector.
11“The Pharisee stood and was praying this to himself: ‘God, I thank You that I am not like other people: swindlers, unjust, adulterers, or even like this tax collector.
12‘I fast twice a week; I pay tithes of all that I get.’
13“But the tax collector, standing some distance away, was even unwilling to lift up his eyes to heaven, but was beating his breast, saying, ‘God, be merciful to me, the sinner!’
14“I tell you, this man went to his house justified rather than the other; for everyone who exalts himself will be humbled, but he who humbles himself will be exalted.”
It would be a healthy exercise to see how the Covenant of Grace works, serves, blesses, because we are now under the Covenant of Grace and not Covenant of Law, what Paul meant when he said you are under Grace, not Law.
