What did God command Noah to do? Because he did what God commanded him to do, his faith was shown to be a living faith. What did God command Abraham to do? Because Abraham obeyed what God commanded him to do, his faith was shown to be a living faith.
If you go back to post #373, you'll see that I've allready addressed this.
It seems to me that if, as I said, God's standard of righteousness hasn't changed in the 3500 or so years since Moses' time, then it's logical to assume that it hadn't changed for the previous 400 or so years since Abraham.
God's standard has never changed. He commanded Noah, Abraham and others to do the same things he commanded Moses to do, the difference was that they didn't write it down in any form we still have today. Let's look at a few examples that show this.
The Sabbath command is first recorded in Ex. 20:8, but if we look back to Ex. 16, we see this:
On the sixth day they gathered twice as much bread, two omers each. And when all the leaders of the congregation came and told Moses, he said to them, “This is what the Lord has commanded: ‘Tomorrow is a day of solemn rest, a holy Sabbath to the Lord; bake what you will bake and boil what you will boil, and all that is left over lay aside to be kept till the morning.’” (Ex. 16:22-23 ESV)
The people already knew they weren't supposed to work on the Sabbath, before God gave the 10 commandments.
The dietary laws weren't recorded until Lev. 11, but look what God says to Noah:
Then the Lord said to Noah, “Go into the ark, you and all your household, for I have seen that you are righteous before me in this generation. Take with you seven pairs of all clean animals, the male and his mate, and a pair of the animals that are not clean, the male and his mate, and seven pairs of the birds of the heavens also, male and female, to keep their offspring alive on the face of all the earth. (Gen. 7:1-3 ESV)
Noah knew about clean and unclean animals.
We can go even further back than that. The various regulations on how to offer a proper sacrifice are given in Leviticus. But if we go all the way back to Gen. 4, we see that Cain and Abel already knew how to offer proper sacrifices. Able obeyed what God had told them about sacrifices, but Cain didn't. Neither one of them wrote it down for us to read.
When talking about Cain and Abel, most people concentrate on the murder. But there's a part that comes right after the sacrifices that most people seem to overlook.
In the course of time Cain brought to the Lord an offering of the fruit of the ground, and Abel also brought of the firstborn of his flock and of their fat portions. And the Lord had regard for Abel and his offering, but for Cain and his offering he had no regard. So Cain was very angry, and his face fell. The Lord said to Cain, “Why are you angry, and why has your face fallen? If you do well, will you not be accepted? And if you do not do well, sin is crouching at the door. Its desire is for you, but you must rule over it.” (Gen. 4:3-7 ESV)
God spoke to Cain about sin as if he already knew what that meant. Yet, in I John 3:4, we are told that it is the law given at Mt. Sinai that defines what sin is. How can this be? Simple. God had already given Cain and the others alive at that time a moral code to live by. Since it wasn't written down, the only thing we know about that code is that it prohibited murder and defined what a proper sacrifice looks like. From the use of the word "sin" above, we may deduce that it also included other laws. Since God never changes and His standards never change, that law that He gave to Cain cannot have contradicted the law He gave on Mt. Sinai. God commanded Cain to obey the same moral code He commanded Moses to follow. They all obeyed the same commandments.