Actually there is...
Gen 26:5 Because that Abraham obeyed my voice, and kept my charge, my commandments, my statutes, and my laws.
And the word for Laws here is...
H8451
תּרה תּורה
tôrâh tôrâh
to-raw', to-raw'
From H3384; a precept or statute, especially the Decalogue or Pentateuch: - law.
scripture actually -tells us- the commands and laws and statutes God gave to abraham...
genesis 12:1..."The Lord had said to Abram, '
Go from your country, your people and your father’s household to the land I will show you."
genesis 13:17..."
Go, walk through the length and breadth of the land, for I am giving it to you."
genesis 15:1..."After this, the word of the Lord came to Abram in a vision: '
Do not be afraid, Abram. I am your shield, your very great reward.'"
genesis 15:9..."So the Lord said to him, '
Bring me a heifer, a goat and a ram, each three years old, along with a dove and a young pigeon.'"
genesis 17:1..."When Abram was ninety-nine years old, the Lord appeared to him and said, 'I am God Almighty;
walk before me faithfully and be blameless."
genesis 17:9-14..."Then God said to Abraham, 'As for you,
you must keep my covenant, you and your descendants after you for the generations to come. This is my covenant with you and your descendants after you, the covenant you are to keep:
Every male among you shall be circumcised.
You are to undergo circumcision, and it will be the sign of the covenant between me and you. For the generations to come
every male among you who is eight days old must be circumcised, including those born in your household or bought with money from a foreigner—those who are not your offspring. Whether born in your household or bought with your money,
they must be circumcised. My covenant in your flesh is to be an everlasting covenant. Any uncircumcised male, who has not been circumcised in the flesh, will be cut off from his people; he has broken my covenant.'"
genesis 17:15..."God also said to Abraham, 'As for Sarai your wife,
you are no longer to call her Sarai; her name will be Sarah."
genesis 21:12..."But God said to him, “
Do not be so distressed about the boy and your slave woman.
Listen to whatever Sarah tells you, because it is through Isaac that your offspring will be reckoned."
genesis 22:2..."Then God said, '
Take your son, your only son, whom you love—Isaac—and go to the region of Moriah.
Sacrifice him there as a burnt offering on a mountain I will show you.'"
genesis 22:12..."'
Do not lay a hand on the boy,' he said. '
Do not do anything to him. Now I know that you fear God, because you have not withheld from me your son, your only son.'"
there is not one word about the sabbath in -any- of the commands God gave to abraham...
you can try all you want to find your idol on every page of scripture...but the fact is that scripture records absolutely no command regarding the sabbath until exodus 16:23...