Romans 4:3

In Paul’s day many of the rabbis taught that Abraham experienced justification because of his obedience rather than because of his faith. [Note: Harrison, p. 47. Cf. 1 Maccabees 2:51.] They also taught that Abraham had a surplus of merit that was available to his descendants, the Jews. [Note: Robertson, 4:350; Witmer, p. 453. Cf. Luke 3:8.] Consequently the apostle went back to Genesis 15:6 for his authority.

Exactly what Abraham believed is not clear in Genesis 15. The Hebrew conjunction waw used with a perfect tense verb, as in Genesis 15:6, indicates a break in the action. A good translation is, "Now he [Abram] had believed . . ." Abraham had obviously believed God previously (cf. Genesis 12:1-4; Genesis 12:7; Genesis 14:22-24). However now Abraham learned that he would receive an heir from his own body and innumerable descendants (Genesis 15:4). He believed this too. Exactly what Abraham believed is incidental to Paul’s point, which was that he trusted God and, specifically, believed God’s promise.

". . . Abraham just believed God: gave Him the honor of being a God of truth." [Note: Newell, p. 139.]

Trust in God’s promise is what constitutes faith and results in justification. The promises of God vary. These promises constitute the content of faith. The object of faith does not vary, however. It is always the person of God. For us God’s promise is that Jesus Christ died as our substitute and satisfied all of God’s demands against sinners (Romans 3:24-25).

Note that God credited Abraham’s faith to him as righteousness (Romans 4:3). Faith itself is not righteousness. Faith is not meritorious in itself. It is only the vehicle by which God’s righteousness reaches us. However, it is the only vehicle by which it reaches us.