Paul waits to explain righteousness through faith (see 3:21) until he first teaches about the sinfulness of all people. Both non-Jews and Jews are equally under the power of sin (1:18–32; 2:1–3:8). Because of this, both groups are in the same situation before God. No one can gain God’s favor by their own actions or obedience (3:9–20). All people need God’s saving action, not their own efforts.