Gen. 9:9 a everlasting covenant.

We may miss something by reading that God made a covenant with Noah with a rainbow. Also really 2 things.
1.  in Gen. 9:16  tells us more.  it is called a everlasting covenant.
2. in 9:9  we see that it is for his seed after him.
Noah is all that is left.  He is the restoration and new beginning.  His seed will be Abraham. So to Abraham we have the seed continuing.  We see that the seed was in Noah.  He has in him that everlasting covenant.  In Gen. 17:7 and 13  show us that Abraham has it now.  The difference is that God creates out of Abraham the new nation.  Noah is all alone, many people came from him. Must be able to say Abraham is in his line.

First God was saying when I see the bow---now he begins to say when I see the blood. Ex.12:13.  When God sees something in this situation, he sees tremendous things. They all point to his special covenant.  A little side here. The word testament means covenant.   We are under the new covenant of his will.

The seed that will eventually come forth is the one that came forth in Mary's womb.
Heb. 13:20  we have the everlasting covenant in Christ's blood.
the seed is Jesus, he is the one who gives us the everlasting covenant through his holy blood.
Jn. 14:16-17  This points to the fact that he can be in you.  That would mean that the seed which is Christ shall be in you. the everlasting covenant shall be in you.
Col. 1:27  Christ in you the hope of glory.
Gal.3:29  if you be Christ's then you are Abraham's seed.  if you are heirs of God then he is yours and then you have all that he is.  All the blessings given to Abraham are the same for us.  God becomes your possession and you his.  That is why we are called the bride. We become in union with God just like a marriage. No divorse  unless we give him up.  Other wise we are bonded together permanently. That is what covenant is all about. 
That is what happens when you marry. You share all you have with the other partner.  There still remains respect for one anothers belongings. Don't just take it but ask.  We ask the father in Jesus name for what we need. Jn. 15:16. 
All the promises of God are yes and amen. 2Cor. 1:20  That is in him--Jesus.
could go on in this for a long time but remember that the everlasting covenant is our gift from God.