B'resheet 15:1 After these things the word of the L-RD came to Abram in a vision, saying, "Do not fear, Abram, I am a shield to you; Your reward shall be very great."
After these things - This comment seems to refer back to the events of chapter 14.
A vision - occurs when you are a wake, unlike a dream that occurs when you are asleep.
I am a shield to you - G-d is reminding Abram that He will protect him. Perhaps there was the possibility that the kings from the east would return and attack Abram.
Your reward - Abram passed on taking the spoils of war. HaShem will reward him far beyond his wildest dreams.
We have Divine presence and support, which corresponds to the fifteen letter of the Hebrew alphabet - Samech.
B'resheet 15:2 And Abram said, "O L-rd G-D, what will You give me, since I am childless, and the heir of my house is Eliezer of Damascus?" And Abram said, "Since You have given no offspring to me, one born in my house is my heir."
Abram has one thing on his mind. He is an old man with no children, specifically a male heir to inherit his great wealth and the promises that G-d gave him. Abram and Sarai don't want any more material wealth they want a baby.
It was the custom of the day that a childless couple would adopt one of their servants to inherit their estate.
B'resheet 15:4 Then behold, the word of the L-RD came to him, saying, "This man will not be your heir; but one who shall come forth from your own body, he shall be your heir."
from your own body - G-d assures Abram that he will be a father.
Abram - the name Abram means "exalted father". This must have been a tough name to have when you are childless.
B'resheet 15:5 And He took him outside and said, "Now look toward the heavens, and count the stars, if you are able to count them." And He said to him, "So shall your descendants be."
Count the stars - Have you ever tried this? You need to be outside of town, far away from the city lights on a clear night. You will be amazed at the number of stars in the night sky.
B'resheet 15:6 Then he believed in the L-RD; and He reckoned it to him as righteousness.
Abram was reckoned righteous because of his faith! Abram believed G-d would give him a son. Remember that Abram represents the Father.
Do you believe that the Father has a Son?
We are reckoned righteous because of our trust in G-d's only son Yeshua who was sent to be an offering for us not unlike Isaac.
Rom 4:9-25 Is this blessing then upon the circumcised, or upon the uncircumcised also? For we say, "Faith was reckoned to Abraham as righteousness." How then was it reckoned? While he was circumcised, or uncircumcised? Not while circumcised, but while uncircumcised; and he received the sign of circumcision, a seal of the righteousness of the faith which he had while uncircumcised, that he might be the father of all who believe without being circumcised, that righteousness might be reckoned to them, and the father of circumcision to those who not only are of the circumcision, but who also follow in the steps of the faith of our father Abraham which he had while uncircumcised. For the promise to Abraham or to his descendants that he would be heir of the world was not through the Law, but through the righteousness of faith. For if those who are of the Law are heirs, faith/trust is made void and the promise is nullified; for the Law brings about wrath, but where there is no law, neither is there violation. For this reason it is by faith, that it might be in accordance with grace, in order that the promise may be certain to all the descendants, not only to those who are of the Law, but also to those who are of the faith of Abraham, who is the father of us all, (as it is written, "A father of many nations have I made you") in the sight of Him whom he believed, even G-d, who gives life to the dead and calls into being that which does not exist. In hope against hope he believed, in order that he might become a father of many nations, according to that which had been spoken, "So shall your descendants be." And without becoming weak in faith he contemplated his own body, now as good as dead since he was about a hundred years old, and the deadness of Sarah's womb; yet, with respect to the promise of G-d, he did not waver in unbelief, but grew strong in faith, giving glory to G-d, and being fully assured that what He had promised, He was able also to perform. Therefore also it was reckoned to him as righteousness. Now not for his sake only was it written, that it was reckoned to him, but for our sake also, to whom it will be reckoned, as those who believe in Him who raised Yeshua (Jesus) our L-rd from the dead, He who was delivered up because of our transgressions, and was raised because of our justification. NAS
B'resheet 15:7-8 And He said to him, "I am the L-RD who brought you out of Ur of the Chaldeans, to give you this land to possess it." And he said, "O L-rd G-D, how may I know that I shall possess it?"
Abram asks the L-rd for a sign.
B'resheet 15:9-11 So He said to him, "Bring Me a three year old heifer, and a three year old female goat, and a three year old ram, and a turtledove, and a young pigeon." Then he brought all these to Him and cut them in two, and laid each half opposite the other; but he did not cut the birds. And the birds of prey came down upon the carcasses, and Abram drove them away.
The custom of the day was for the two parties who made the contract to state the terms of the contract. Then they would join hands and walk between the two halves of the carcasses. This was the same as us signing a contract at the local courthouse. Jeremiah refers to this custom.
Yirmeyahu (Jeremiah) 34:17-20 "Therefore thus says the L-RD, 'You have not obeyed Me in proclaiming release each man to his brother, and each man to his neighbor. Behold, I am proclaiming a release to you,' declares the L-RD, 'to the sword, to the pestilence, and to the famine; and I will make you a terror to all the kingdoms of the earth. 'And I will give the men who have transgressed My covenant, who have not fulfilled the words of the covenant which they made before Me, when they cut the calf in two and passed between its parts-- the officials of Judah, and the officials of Jerusalem, the court officers, and the priests, and all the people of the land, who passed between the parts of the calf-- and I will give them into the hand of their enemies and into the hand of those who seek their life. And their dead bodies shall be food for the birds of the sky and the beasts of the earth.