I understand that you're 'trying'... to apply the idea of oaths to what God promised to Abraham, which that would mean the law was involved, when the law was definitely NOT involved. And Apostle Paul showed in Romans 4 why that is.
You don't understand what the discussion is about. The law involved with Abraham, Isaac and Jacob concerns the
law of faith, as distinct from the law of works.
Ro 3:27 Where is boasting then? It is excluded.
By what law? of works? Nay: but by the law of faith.
Abraham, Isaac and Jacob were not a party to the law of Works, as they were not party to the Sinai covenant (kingdom of priests).
De 5:3 The LORD
made not this covenant with our fathers, but with us, even us, who are all of us here alive this day. Not only were they not subject to the law of the Sinai covenant, neither were the 12 Patriarchs.
Now I may not be correct about all of this, but I have presented plenty of evidence for it from the scriptures. But the two covenants made with Abraham are distinct IMO. The first covenant in Genesis 15 was not concerning any of his seed prior to the fourth generation.
Ge 15:16 But in
the fourth generation they shall come hither again: for the iniquity of the Amorites is not yet full.
This excludes Isaac, Jacob, Joseph and his brethren. Why Joseph took an oath of the children of Israel to take up his bones when God visited them. Two distinct covenants. No I am speaking of the law of Faith, vs the law of Moses which over four hundred years later. I don't know why it seems everyone makes those two covenants into one. Paul speaks of two covenants distinctly, and so does Hebrews. So too does the law itself.
Read it yourself. Note the bolded.
Gen 15:13 And he said unto Abram, Know of a surety that
thy seed shall be a stranger in a land that is not theirs, and shall serve them; and they shall afflict them four hundred years;
14 And also that nation, whom they shall serve, will I judge: and afterward shall
they come out with great substance.
15 And
thou shalt go to thy fathers in peace; thou shalt be buried in a good old age.
16 But in
the fourth generation they shall come hither again: for the iniquity of the Amorites is not yet full.
This says nothing About anybody coming to the land except the forth generation of his seed. In fact Abraham is specifically told he will
die and be buried. Nothing about God being their (his seeds) God etc.
Gen 15:16 But in the fourth generation
they shall come hither again: for the iniquity of the Amorites is not yet full.
Where is God covenanting here to give the land to
him? It is to the fourth generation it is given. Acts 7:5 Read it.
And
he gave him none inheritance in it, no, not so much as to set his foot on:
yet he promised that he would give it to him for a possession, and to his seed after him, when as yet he had no child.
Hebrews is even more thorough in this IMO.
Gen 15:18 In the same day the LORD made a covenant with Abram, saying,
Unto thy seed have I given this land, from the river of Egypt unto the great river, the river Euphrates:
19 The Kenites, and the Kenizzites, and the Kadmonites,
20 And the Hittites, and the Perizzites, and the Rephaims,
21 And the Amorites, and the Canaanites, and the Girgashites, and the Jebusites.
My take on this and Hebrews is The covenant made in Genesis 15 concerns
his natural Seed. Genesis 17 concerns the
Royal seed The kingdom promised Abraham.
But you are not seeing anything else in my posts but Moses law, and works.
I am not dispensationalist BTW.
The two inheritances only become one for the firstborn. Those which have both portions of inheritance