Not To Be Confused With
Imputed righteousness (credited to us, a legal standing) is the classic Protestant emphasis; infused righteousness (a grace poured in that makes us actually righteous) is the classic Catholic emphasis — a core hinge of the justification debate.
The bookkeeping word of justification: God “counts” (logizomai) — Abraham's faith counted as righteousness (Rom 4), our sin counted to Christ, his righteousness counted to us (2 Cor 5:21). The traditions divide over whether righteousness is reckoned, infused, or both.