Paul now proceeds to illustrate justification by faith apart from the law and works of the law in Romans 3, and uses the examples of Abraham and David, two ancestors of whom the Jews were especially proud.

William Newell explains that...

"THE JEWS ESPECIALLY gloried in Abraham and David, -just as we all naturally glory in the assumed personal righteousness of great saints, as the ground of God's favor to them. But whatever blessing, says Paul, Abraham obtained, Scripture forbade the thought that he could glory before God; because he simply believed what God told him, that his seed should be in number like the stars of heaven. (Read Ge 15:6) Abraham gave God His proper glory as the God of truth. We cannot conceive of Abraham as boasting before his house and before the Hittites that he had performed an act creditable to himself in believing God!" (Newell, William: Romans Verse by Verse)

"What then" (oun) in inductive Bible study is referred to as a term of conclusion and can also be translated "therefore". This term of conclusion connects the following argument with what Paul has been talking about in the third chapter. In the preceding chapter Paul had asked several rhetorical (for effect not expecting an answer) questions:

Where is boasting? (Romans 3:27-28)

Was God the God of the Jews only or of the Gentiles also? (Romans 3:29-30)

Was the Law was nullified by salvation by faith? (Romans 3:31)

Rephrased, this verse would read

"Therefore, what shall we say that Abraham, our first father, has found according to the flesh, that is, by natural human effort?"

Paul appears to be utilizing a style of teaching referred to as "diatribe" which was no uncommonly used in ancient philosophical schools and is  characterized by rhetorical questions and imaginary interlocutors. Diatribes typically would include rhetorical questions such as “What shall we say then?” to mark transition to the next point.

"What then shall we say" is a rhetorical question, an approach which Paul is fond of (Ro 4:1; 6:1; 7:7; 8:31; 9:14, 30). In Romans he often uses this method in anticipation of an objection or to propose an inference. The rhetorical approach is used only by Paul in Romans in its "argumentative" portions (the first 11 chapters) and is not used in the last five chapters, which are exhortational.

The design of the first part of this chapter is to answer some of the objections which might be offered by a Jew to the statements in the preceding chapters. The first objection is stated in this verse. A Jew would naturally ask, if the view which Paul had stated was correct, what benefit could the Jew derive from his religion? This question is practically the same as in Chapter Three, "What advantage, then, has the Jew ?"

Paul like any good teacher then proceeds to illustrate the abstract truth of justification by faith apart from works (which he had just summarized in Ro3:21-31) using the example of faith in action in the life of Abraham (and David).

According to Jewish law, a question was settled by two or three witnesses. Paul calls two witnesses ("the Law and the Prophets" in Ro 3:21- note) from the OT to testify to justification through faith. In Romans 4 he brings these two witnesses to the stand so to speak, calling on "father Abraham" from the Law and the beloved David who was not only a king but a prophet, as attested by Peter in his sermon to the Jews at the feast of Pentecost, in which he declared

"Brethren, I may confidently say to you regarding the patriarch David that he both died and was buried, and his tomb is with us to this day... he was a prophet, and knew that GOD HAD SWORN TO HIM WITH AN OATH TO SEAT one OF HIS DESCENDANTS UPON HIS THRONE." Acts 2:29-30)

F. Godet in his classic commentary on Romans puts it this way...

Abraham being for the Jews the embodiment of salvation, his case was of capital moment in the solution of the question here treated. This was a conviction which Paul shared with his adversaries. Was the patriarch justified, by faith and by faith alone, his thesis was proved. Was he justified by some work of his own added to his faith, there was an end of Paul's doctrine. In the first part of this chapter, Ro 4:1-12, he proves that Abraham owed his righteousness to his faith, and to his faith alone. In the second Ro 4:13-16, he supports his argument by the fact that the inheritance of the world, promised to the patriarch and his posterity, was conferred on him independently of his observance of the law. The third part, Ro 4:17-22, proves that that very posterity to whom this heritage was to belong was a fruit of faith. In the fourth and last part, Ro 4:23-25, this case is applied to believers of the present. Thus righteousness, inheritance, posterity , everything, Abraham received by faith; and it will be even so with us , if we believe like him." (Godet, Frederick Louis: The Epistle of St Paul to the Romans)

Moule in another classic work on Romans explains why Paul would choose Abraham at this point in his argument, writing that as "father Abraham"...

"...moves across the scene of Genesis, we — even we Gentiles — rise up as it were in reverent homage, honoring this figure at once so real and so near to the ideal...walking with God Himself in a personal intercourse so habitual, so tranquil, so congenial. Is this a name to becloud with the assertion that here, as everywhere, acceptance was hopeless but for the clemency of God “gift-wise, without deeds of law”? Was not at least Abraham accepted because he was morally worthy of acceptance? And if Abraham, then surely, in abstract possibility, others also. There must be a group of men, small or large, there is at least one man, who can “boast” of his peace with God." On the other hand, if with Abraham it was not thus, then the inference is easy to all other men. Who but he is called “the Friend” (2Chronicles 20:7, Isaiah 41:8)? Moses himself, the almost deified Lawgiver, is but “the Servant,” trusted, intimate, honoured in a sublime degree by his eternal Master. But he is never called “the Friend.” That peculiar title seems to preclude altogether the question of a legal acceptance. Who thinks of his friend as one whose relation to him needs to be good in law at all? The friend stands as it were behind law, or above it, in respect of his fellow. He holds a relation implying personal sympathies, identity of interests, contact of thought and will, not an anxious previous settlement of claims, and remission of liabilities. If then the Friend of the Eternal Judge proves, nevertheless, to have needed Justification, and to have received it by the channel not of his personal worth but of the grace of God, there will be little hesitation about other men’s need, and the way by which alone other men shall find it met." (Moule, H C G, Frederick Louis: The Epistle of St Paul to the Romans)
 

David Stern in his "Jewish NT Commentary" comments that

"There can be no doubt that in the 1st century c.e. the doctrine was widespread that descendants can benefit and even can claim salvation on the ground of their ancestors’ righteousness. Yeshua’s opponents made exactly such a claim at (In Jn 8:33 after Jesus had told His audience that if they the truth would set them free, the Jews "answered Him" saying "We are Abraham's offspring, and have never yet been enslaved to anyone; how is it that You say, 'You shall become free'?"), Paul’s own opponents obviously were making use of the idea at [ Paul wrote "Are they Hebrews? So am I. Are they Israelites? So am I. Are they descendants of Abraham? So am I." 2Cor 11:22]. Rabbinic literature does well in pointing up Avraham’s faithful and trusting attitude toward God. For example, the Midrash Rabbah records:
 

“In the 'olam haba [world to come] Israel will sing a new song, as it is said, ‘Sing unto Adonai a new song, for He has done marvelous things’ (Ps98:1). By whose z'khut [merit] will they do so? By the merit of Avraham, because he TRUSTED in the Holy One, blessed be he, as it says, ‘And he TRUSTED in Adonai’ (Ge15:6).” (Exodus Rabbah 23:5)

The present chapter (Romans 4) investigates the nature of Avraham’s own “merit”: what is it that he obtained by his own efforts?... Didn’t he have “works,” meritorious “deeds” that earned him his salvation? This is what Paul’s hypothetical questioner is asking." (Jewish NT Commentary)

THAT ABRAHAM, OUR FOREFATHER ACCORDING TO THE FLESH HAS FOUND: Abraam ton propatora hemon heurekenai (RAN) kata sarka: (Isa 51:2; Mt 3:9; Lu 3:8; 16:24,25,29-31; Jn 8:33,37-41,53,56; Ac13:26; 2Co11:22) (16; Heb12:9)

The Jew might remind Paul that Abraham had righteousness and thus the question naturally arises as how did he become righteous? Note Paul's use of the term "our" ("our forefather") which identifies Paul with the Jewish audience.

Forefather (Note Strong's # 4310 is not correct for propater) (propater from pro = before + pater = father) is used only here in the NT and refers to the primary founder of a family, the ancestor, the archetypal founder or the ultimate ancestor.

As discussed above, Paul uses the example of Abraham to prove justification by faith because the Jews held him up as the supreme example of a righteous man. For example in His discussion of discipleship with the Jews who had believed in Him explained...

"I speak the things which I have seen with My Father; therefore you also do the things which you heard from your father." They answered and said to Him, "Abraham is our father." Jesus said to them, "If you are Abraham's children, do the deeds of Abraham." (John 8:38-39)

An accurate understanding of how Abraham received righteousness shows how Judaism's works based righteousness had deviated far from the faith based righteousness.

Paul also would have been very familiar with the rabbinical literature which taught that Abraham was the ultimate example of a man who was justified by works. In the verses that follow, Paul, like a prosecuting attorney, will demonstrate beyond a shadow of a doubt that, to the contrary, the Holy Scriptures clearly teach that Abraham was saved by his faith alone independent of his works.

As translated by the NASB and the NIV (see Vine's note in next paragraph), the phrase "Our forefather according to the flesh" speaks of the physical line of Abraham. The Jews traced their lineage to "father Abraham". God cut  covenant with Abraham in Genesis 15 and again ratified the covenant with Isaac who passed it on to Jacob, whose name was later changed to Israel. Israel had twelve sons who became the fathers of the twelve tribes of Israel. In Paul's day anyone who was born Jewish could trace their lineage through one of the 12 tribes and ultimately back to Abraham. Before his rebirth, Paul was proud of the fact  that he "of the nation of Israel, of the tribe of Benjamin, a Hebrew of Hebrews."  (see note Philippians 3:5) The typical Jew in Paul's day was proud of their lineage and especially proud that they could trace their bloodline all the way back to "father Abraham".

Vine writes that

"The phrase “according to the flesh” can be taken grammatically either with “our forefather” or with “hath found.” Opinions regarding the choice differ. If the latter connection is taken (as does NKJV), the question asks what righteousness Abraham obtained by works, that is, by natural effort and attainment. This is in keeping with what follows in (v2). If the phrase is connected with “our forefather,” (as in NASB, NIV) it signifies natural relationship in contrast to the spiritual relationship established by faith, a contrast stressed in (v11,12)." (Vine, W. Collected writings of W. E. Vine. Nashville: Thomas Nelson )

Considering the aberrant teaching of the rabbis (see examples below) it is not surprising that many of the first century Jews believed they possessed salvation solely on the basis of being Abraham's offspring. In addition, they thought that they determined who was eligible for salvation, because they owned it! Before the coming of Christ, they shared "salvation" (or what they thought was salvation) only with those willing to become Jewish proselytes. When proselytes converted to Judaism, they were instructed to be circumcised and to place under obedience to the Law of Moses. It is surprising to discover that there are many non-Jews today who still feel that in the OT for one to be "saved" they must enter into salvation via Judaism. Nothing could be further from the truth, but this misconception does reflect how good their Jewish "propaganda" has been, even among evangelicals who should know better -- God's righteousness has always been reckoned only on the basis of faith - Sola Fide -- and does not require one to join a particular church or carry out any act (including baptism). Justification is a gift graciously given by God to undeserving sinners.

Jesus became perfect man "according to the flesh" (1:3) that we might be made righteous according to His Spirit.

Found (2147) (heurisko) means to learn the location of something, either by intentional searching or by unexpected discovery learn whereabouts of something. It means to find, discover, come upon, happen to find, to learn something previously not known, frequently involving an element of surprise.

Heurisko is the source of our English word eureka from an exclamation attributed to Archimedes on discovering a method for determining the purity of gold.

Barclay explains Paul's introduction of Abraham remarking that

"Paul begins to speak about Abraham because he was a wise teacher who knew the human mind and the way it works. He has been talking about faith. Now faith is an abstract idea. The ordinary human mind finds abstract ideas very hard to grasp. The wise teacher knows that every idea must become a person, for the only way in which an ordinary person can grasp an abstract idea is to see it in action, embodied in a person. So Paul, in effect, says, "I have been talking about faith. If you want to see what faith is, look at Abraham."

Barclay adds these comments regarding how the Rabbis dealt with Abraham:

"Some few, some very few, of the more advanced Rabbis believed that (that it was purely Avraham's faith which made him a good man in God's sight) There was a rabbinic commentary which said, "Abraham, our father, inherited this world and the world to come solely by the merit of faith whereby he believed in the Lord; for it is said, 'And he believed in the Lord, and he accounted it to him for righteousness.'" Sadly however the great majority of the Rabbis altered the Genesis account of Abraham to match their own beliefs. They held that because Abraham was the only righteous man of his generation, therefore he was chosen to be the ancestor of God's special people. The immediate answer is, "But how could Abraham keep the law when he lived hundreds of years before it was given?" The Rabbis response was an odd theory that Abraham kept the Law by intuition or anticipation. For example we read in the the Apocalypse of Baruch (57:2 ) "At that time, the unwritten law was named among them, and the works of the commandment were then fulfilled." Ecclesiasticus (44:20, 21 ) says that Abraham "kept the law of the Most High and was taken into covenant with God...Therefore God assured him by an oath that the nations should be blessed in his seed." The Rabbis were so attached to their theory of salvation by works that they insisted that it was because of his works that Abraham was chosen, although it meant that they had to argue that he knew the law by anticipation, since it had not yet come!

John MacArthur writes that

"In a hypothetical syllogism, Paul says, For if Abraham was justified by works, then he has something to boast about. The major premise is that, if a man could be justified before God by his own human efforts, then he has ground for boasting in himself. The minor premise is that Abraham, as a man, was justified by works. The necessary conclusion would be that Abraham therefore has something to boast about. The major premise is true: If a man could be justified by works, he would indeed have something to boast about, because he would have merited his own salvation. But, as Paul goes on to demonstrate, the minor premise is not true. Consequently, the conclusion is untrue. Abraham did not have anything in himself to boast about before God." (MacArthur , J: Romans. Moody Press)

One pastor writes:

"If" (1487) (ei) is referred to in Greek as a condition of the first class, which means that what follows is assumed as true. In the present context it is assumed true for the sake of argument (though it is in fact not actually true - now are you confused?).

Wuest's translation may help you see the meaning of the "if"...

"For, assuming that Abraham was justified out of a source of works, he has ground for boasting, but not when facing God."

Justified (1344) (dikaioo is derived from the noun dike = righteousness) (Click more detailed analysis of dikaioo) defines the act by which a man is brought into a right state as related to God. Justified means "being declared righteous." Note that verbs which end in –óo generally indicate bringing out that which a person is or that which is desired, but not usually referring to the mode in which the action takes place. 

Dikaioo never means to make anyone righteous or to do away with his violation of the law, by himself bearing the condemnation and the imposed sentence. Abraham or any man in his fallen condition can never do anything in order to pay for his sinfulness and thus be liberated from the sentence of guilt that is upon him as it happens in the world - when a guilty person has paid the penalty of a crime, he is free from condemnation.

In regard to Biblical righteousness, God is the objective standard which determines the content of meaning of dikaios and at the same time keeps that content of meaning constant and unchanging, since He is the unchanging One. Righteousness in the biblical sense is a condition of rightness the standard of which is God, which is estimated according to the divine standard, which shows itself in behavior conformable to God, and has to do above all things with its relation to God, and with the walk before Him.

Paul's statement in this verse ("Abraham was justified by works") may bring to your mind James' question "Was not Abraham our father justified by works, when he offered up Isaac his son on the altar?" This question in Greek expects a "Yes"! So how is this seeming contradiction to be resolved. The point is that Abraham was justified by faith in God's Word, but he then demonstrated that his faith was genuine by his works. The justification by works of which James is speaking is a different "type of justification". James is referring to justification before other people. Stated another way, James is using the word dikaioo or  justified to mean “proved.” We prove to others our genuine faith in Christ through our works. But the justification that comes through faith is before God, and we do not “prove” ourselves to Him by our works (as Paul is explaining in this section of Romans). Instead, God declares us righteous (dikaioo) through our faith in and our association with Christ, the One who died for our sins. Paul has already declared "that a man is justified (declared righteous) by faith apart from works of the Law." (see note Romans 3:28). In summary, Abraham was justified before God by faith but was justified (proved) before men by his works (James 2:21-24).

The rabbis taught a doctrine in which the merits ("works") of Abraham (who they taught had a superfluity of meritorious "credits") would be passed on to the Jews.

HE HAS SOMETHING TO BOAST ABOUT: echei (3SPAI) kauchema: (Ro 3:27; 15:17; Ezek 8:9; Jer 9:23,24; 1Cor 9:16; 2Cor 5:12; 11:12,30; 2Cor 12:1-9; Gal 6:13,14; Eph 2:9)

Boast about (2745) (kauchema noun related to the verb kaucháomai = to boast <> in turn akin to aucheo = boast + euchomai = express a wish <> in turn from auchen = neck, which vain persons are apt to carry in proud manner) means not the actual boasting itself but the ground of glorying or boasting.

Kauchema is not connected with the word glory (doxa) which is used of God’s glory. It means glory in the sense of exultation or self-congratulation. Kauchema describes the matter or ground of boasting. In this context the ground of Abraham's boasting would have been that he was declared righteous because of his works.

If Abraham’s own works had been the basis of his justification, he would have had every right to boast in God’s presence.

"Justified" by works -- A preacher who had long-departed from the truth of the gospel, told the following story to summarize "the faith" he taught.

It seems that a frog one day fell into a pail of milk, and though he tried every conceivable way to jump out, he always failed. The sides were too high, and because he was floating in the milk he could not get enough leverage for the needed leap. So he did the only thing he could do. He paddled and paddled and paddled some more. And voila! His paddling had churned a pad of butter from which he was able to launch himself to freedom. The preacher’s conclusion was "Just keep paddling, keep on working, keep on doing your best, and you will make it." You may smile at this exaggerated simplification, but this actually describes the "good news" promulgated by many churches and by every non-Christian religion in the world. It is amazingly sad that  “Amazing Grace” is one of the favorite hymns worldwide and yet most of these same people reason that if you just do your best you will somehow make it to Heaven. The truth is that mankind, be he Jew or Gentile, is deeply hostile to the truth of justification by faith alone through God’s grace. Most people are much more comfortable with the motto “We get our salvation the old-fashioned way. We earn it!” This is exactly the falsehood Paul is addressing in this section.
 

As alluded to earlier in this section, among the Jews, Abraham was felt to be the prime example and model of a man who was justified by his works, and this false understanding was amply supported by the rabbinic literature of the day as illustrated below:

For example, the Mishnah’s third division Kiddushin (4.14) makes a specious interpretation of Ge26:5, in which God repeats His covenant promise to Abraham's son Isaac, declaring...

"And I will multiply your descendants as the stars of heaven, and will give your descendants all these lands; and by your descendants all the nations of the earth shall be blessed 5 because Abraham OBEYED Me and KEPT My charge, My commandments, My statutes and My laws."

The Mishnah wrongly concludes
 

“we find that Abraham our father had performed the whole law before it was given, for it is written, ‘Because that Abraham obeyed my voice and kept my charge, my commandments, my statues, and my laws.’

The earlier Book of Jubilees (circa b.c. 100) similarly says,
 

“For Abraham was perfect in all his deeds with the Lord, and well-pleasing in righteousness all the days of his life.”

So perfect was Abraham thought to be that "The Prayer of Manasses" concluded that Abraham had no need of repentance, declaring...
 

“Thou, therefore, O Lord, that art the God of the righteous, hast not appointed repentance unto the righteous, unto Abraham.… ”

Now you can understand why Paul is going to such lengths to refute the preposterous Rabbinical teachings that Abraham performed the whole Law even before it was actually written, that he was perfect in all his deeds, and that he had no need of repentance.

BUT NOT BEFORE GOD: all ou pros ton theon: (Ge 12:12,13,18,20; 20:9-13; Josh 24:2; 1Cor 1:29; 4:7; Gal 3:22)

"from God's point of view Abraham had no basis at all for pride" (NLT)

How might this truth apply to believers? Many Christians after believing on Christ for their eternal destiny fall back into the trap of spending the rest of their lives trying to gain a sense of God's approval and love by hard, exhausting, committed, dedicated labor. And you can never win God's love that way. You never know when you have done enough. You cannot earn the gift of love, but it is yours if you take it by faith in Christ. And this faith obeys. Not perfectly, but the general direction of this person's life is to live in a such a way so as to please God.

William Newell writes that

"To discover that the greatest saints have no other standing than the weakest saints, is a lesson that is difficult for all of us. So now for the Jew to find that great Abraham has nothing in the flesh, but must be justified by simple faith, like any sinner, is a great shock. There was no honor, no "merit, " in Abraham's believing the faithful God, who cannot lie. The honor was God's. When Abraham believed God, he did the one thing that a man can do without doing anything! God made the statement, the promise; and God undertook to fulfill it. Abraham believed in his heart that God told the truth. There was no effort here. Abraham's faith was not an act, but an attitude. His heart was turned completely away from himself to God and His promise. This left God free to fulfill that promise. Faith was neither a meritorious act by Abraham, nor a change of character or nature, in Abraham: he simply believed God would accomplish what He had promised: "In thee shall all the families of the earth be blessed" (Ge 12:3)." (Newell, William: Romans Verse by Verse) (Bolding added)

A survey by the Barna Research Group suggests widespread confusion about the gospel - even among churchgoers who feel responsible to spread the gospel.

George Barna, president of the Barna Research Group aptly comments that "There is plenty of reason for churches to worry if nearly one-half of their people who believe in evangelism also believe in salvation by works! The central message of Protestantism is in salvation by faith alone in Christ, yet many Protestant evangelizers seem to be preaching a different message.” Respondents from “mainline” Protestant churches tended to believe in salvation by works more frequently than those from “evangelical” churches. Yet pastors from mainline churches seemed more confident in their members’ ability to evangelize. Almost half (46%) of mainline pastors believe their congregations are qualified to present the gospel, while only one-fourth (24%) of Baptist pastors do.