Genesis 15:5-6 meaning

God brings Abram out of his tent and says, look toward the heavens and count the stars, if you are able to count them (v 5). God showed Abram the stars indicating the abundance of his descendants (Deuteronomy 1:10). In other words, his descendants will be myriad, more than can be readily numbered. It is not feasible that a person can "count" the stars, but God can number and name them (Psalm 147:4; Isaiah 40:26). So, shall your descendants be (v 5)- In Genesis 13:16 God had promised descendants as numerous as the dust, and here in this verse, as numerous as the stars.

Abram was rewarded for faith in action. But now in verse 6, Abram's belief in a future promise is reckoned to him as righteousness. God promises so shall your descendants be (v 5), referring to the myriad number of stars. And Abram believed in the Lord (v 6); he believed in his heart that what God said was true. God reckoned, or counted Abram as righteous in His sight, solely because of belief. It is faith without action, simply believing that God will fulfill His promise.

There is no external evidence of faith referenced. No future requirement of actions noted. Abram is declared righteous on the spot, solely because he believed. We as onlookers only know Abram believed God's promise at this point in the story because God tells us Abram's heart. If we were not given this insight, we wouldn't know. But God goes out of His way to not only tell us Abram's heart, but also God's response to Abram's heart: to declare Abram righteous in His sight. The apostle Paul quotes this promise to show the nature of Abram's faith, "In hope against hope he believed, so that he might become a father of many nations according to that which had been spoken, 'So shall your descendants be" (Romans 4:18). Abram believed in spite of human experience.

In Paul's letter to the Romans, he uses Genesis 15:6 to support his assertion that righteousness in the sight of God is solely a matter of faith, in contrast to competing Jewish "authorities" who maintained that it was necessary to also follow the Jewish law in order to be righteous in God's sight (Romans 4:2-4). Paul emphasizes that Abram's faith at this point was not connected with a reward for deeds (Romans 4:4). Unlike the opening of this passage where Abram is rewarded for deeds (Genesis 15:1), here he is reckoned as righteous.

Paul makes the same point in his letter to the Galatians, quoting Genesis 15:6 in Galatians 3:6. Paul asserts that all those who believe as Abraham believed are "sons of Abraham" (Galatians 3:7). That includes Gentiles, who were uncircumcised when they believed, just as Abraham was uncircumcised at this point in the Genesis story. Paul further points out that being reckoned as righteous in the sight of God had nothing to do with the Law. For at this point the Law is still four hundred years in the future (Galatians 3:17-18). Paul's writings echo the distinction between rewards for deeds of faith and being reckoned as righteous to be accepted in the sight of God, which is based on faith alone. So according to the story of Abraham and according to Paul's writings, God counts people as righteous purely because of their faith, unrelated to actions. But, he does reward faith in action. We are counted as righteous because of our faith and we are rewarded when we live out that faith. According to this sermon of Stephen's in Acts 7, the first time Abraham believed God and was reckoned as righteous in the sight of God was likely while he was in Ur.

Genesis 15:6 is one of the most significant verses of scripture. Some say it is the key verse of the entire Old Testament. It is quoted four times in the New Testament. Two references have already been noted (Romans 4:3, and Galatians 3:6). The verse is also quoted in Romans 4:22 and James 2:23. This chapter opened addressing fear and concern, but here we have a firm statement that Abram remains steadfast in his faith in God. Abram believed in the Lord that He can and will do what He said. The word "believed" is the Hebrew word aman and means to place trust with confidence. It is a verb form that indicates a completed action; something that has started and finished. There is nothing else required for Abram to be righteous in the sight of God. Abram believed, God declared, the transaction is finalized.

The Hebrew word "Chashab" is sometimes translated into English as reckoned, credited, or counted. It means to assign value. In this case, God assigns Abram's faith, the value of righteousness. The word "righteousness" in Hebrew is tsâdaqah and means "blameless conduct" or one who is in "right standing" with God. In other words, one who has "blameless behavior that conforms to a set standard." Often righteousness is defined in terms of moral conduct. This is the experience of righteousness lived before men. For example, Ezekiel 18:5, "if a man is righteous [and] does what is lawful and right." Next, there is a list of actions prohibited in the Pentateuch (first 5 books of the Old Testament) which the righteous man must refrain from doing (Ezekiel 18:6-9). But here, Abram is not described as "doing" righteousness. This righteousness is not before men, for Abram is not doing anything. He simply believed what God said. Rather, his faith in believing God's promise is being counted, credited or assigned for righteousness. Righteousness in the sight of God cannot be earned. Acceptance by God comes only through believing. Becoming righteous in God's sight is something we receive by faith, not something we can deserve.

Abram's relationship with God was established by his faith in God. God accepted him as righteous because Abram believed. This is only in this way that mankind can be accepted by God

God's acceptance of us is without condition and does not involve deeds. On the other hand, pleasing God and gaining rewards from God requires putting our faith into action (Hebrews 11:6). Believing in God and acting on that belief by faith has always been the way to please God. Cain displeased God while Abel pleased God, because of his actions rooted in faith (Hebrews 11:4). Consider Noah, who "became an heir of the righteousness which is according to faith" because of his faithfulness building the ark (Hebrews 11:7).  While acceptance by God is granted solely by God based on the heart, pleasing God requires putting faith into action. Abraham was rewarded for putting his faith into action. But Abraham was declared righteous solely because he believed, without any deeds.

Righteousness in God's sight is a divine gift to man, not something that he earns or achieves. The Bible shows us this in Ephesians,

"For by grace you have been saved through faith; and that not of yourselves, it is the gift of God; not as a result of works, so that no one may boast"
(Ephesians 2:8-9).

But living a righteous life to be seen before men requires putting faith in action. This is shown in the next verse in Ephesians, 

"For we are His workmanship, created in Christ Jesus for good works, which God prepared beforehand so that we would walk in them"
(Ephesians 2:10).

God accepts us and makes us a new creation in Christ unconditionally, and we receive this amazing gift by faith. The purpose we have as a new creation is to do good deeds which God prepared for us to walk in. And even though God prepared the deeds, He promises us great rewards if we will faithfully carry them out. This pattern is consistent from Genesis to Revelation.

In the cases of Noah and Abram, they were credited with righteousness on the basis of their faith. Like Abram, Noah found grace, or favor in the eyes of the Lord because of his belief (Genesis 6:8). But they were also seen as righteous in the eyes of men, and received great rewards as a result of their deeds. Noah obeyed God and built an ark. Abram obeyed God and was willing to sacrifice Isaac. In each case, they were reckoned as righteous before the deed.

It should be noted that Abram's faith was accounted to him for righteousness before he personally was circumcised as a sign of the covenant with God and more than 400 years before the law was given to his descendants. Before Abram had proved himself righteous by his deeds or obeying laws, he is counted as righteous because of his faith. Therefore, neither circumcision nor the law had a part in Abram's righteousness. Ultimately, all who belong to Christ are Abram's spiritual offspring:

"...it is those who are of faith who are sons of Abraham"
(Galatians 3:7).