Not belonging to God due to sin is spoken of as being far away from God. Belonging to God because of the blood of Christ is spoken of as being brought near to God. Alternate translation: "you who once did not belong to God now belong to God because of the blood of Christ" (See: [[rc://en/ta/man/translate/figs-metaphor]])
The blood of Christ is a metonym for his death. Alternate translation: "by Christ's death" or "when Christ died for us" (See: [[rc://en/ta/man/translate/figs-metonymy]])