Last Sunday I preached out of Romans 3:21-25. Verse 22 states that the righteousness of God is given to have placed their faith in Christ Jesus, and believe. This is one of the several astounding things about the Atonement. William Lane Craig explains here.
"According to Paul, the righteousness of God is given to all who believe in Jesus. In Rom 4 Paul goes on to explain that this gift is accorded by means of “reckoning,” in the sense in which a merchant would settle accounts. [To "reckon" - to consider or regard in a specified way. In this case, to be considered, or specified, as righteous.]
Although it is sometimes said that justification involves merely acquittal and not a positive ascription of righteousness, nothing in the text warrants so diluting the righteousness of God that is reckoned to us. Biblically, the righteousness of God is a rich, variegated property, not a bare absence of guilt. Prima facie God’s righteousness in its full moral rectitude is reckoned to believers (cf. Philip 3.6–9). This seems clearly expressed in II Cor 5.21: “For our sake he made him to be sin who knew no sin, so that in him we might become the righteousness of God.” There is no exegetical warrant for diluting this statement: our sin is credited to Christ’s account and God’s righteousness is credited ours."
(Craig, The Atonement, p. 25)