Abraham ?

[Ormly]

All. Just as was required of Israel.(note that thing ceremonial, such as the passover would not have been part of it)
Genesis 17:9
And God said unto Abraham, Thou shalt keep my covenant therefore, thou, and thy seed after thee in their generations.
Genesis 18:19
For I know him, that he will command his children and his household after him, and they shall keep the way of the LORD, to do justice and judgment; that the LORD may bring upon Abraham that which he hath spoken of him.
It amazes me that person would think that God required of Abraham and us anything difference than that revealed in His commandments.

I can only agree if you say Abraham's righteousness was a law of God unto itself within Abraham that God recognized to become the reason why He chose him. Otherwise I find no specific law of God given Abraham that, by such a law, would have made Abraham the man he was.

If I am correct then of Abraham's own volition he performed by his life that which we believe can only be performed today by one born again of Christ.