It is widely recognised that Paul’s use of the term “righteousness” (δικαιοσύνη) must be understood against the background of the Hebrew equivalents צדק and צדקה. This paper explores the meaning of the Hebrew terminology and identifies various ways in which it has been misunderstood in Pauline scholarship. In particular, it will be argued that the Old Testament evidence does not support the common claim that δικαιοσύνη denotes a relationship with God, either in the sense of a status of justification or in the sense of covenant membership. In non-forensic contexts, צדק and צדקה most commonly denote moral rectitude and morally right behaviour, respectively. The words themselves appear to be rather general and not to encode a specific basis according to which rectitude is assessed, such as conformity to a norm of creation or covenant, satisfaction of the demands of relationships or, as recently suggested by Niehaus, “conformity to God’s Being and doing.” In a forensic context to be צדיק is to be in the right on the merits of the case, not to have been vindicated by the court, and צדקה is one’s objective innocence or just cause, not a status of vindication. Paul’s language of “having” δικαιοσύνη in Phil 3:9 is best understood against the background of the equivalent Hebrew idiom in Deut 6:25; 24:13, where “having” righteousness means having the credit ordinarily belonging to those who have done right. Contrary to what is often argued, the second occurrence of δικαιοσύνη in Phil 3:9 does not denote the believer’s relationship with God; rather, the two occurrences can be understood to have the same meaning, the difference being the basis on which righteousness is credited. Paul’s citation of Ps 32:1-2 in Rom 4:6-8 indicates that he sees the reckoning of δικαιοσύνη to the undeserving as equivalent to the non-reckoning of sin. Although the result is a right relationship with God, what is graciously reckoned is not the relationship but the appropriate moral behaviour which is its prerequisite.