Hebrews 10:10, 12

And in accordance with this will [of God] we [who believe in the message of salvation] have been sanctified [that is, set apart as holy for God and His purposes] through the offering of the body of Jesus Christ (the Messiah, the Anointed) once for all.

whereas Christ, having offered the one sacrifice [the all-sufficient sacrifice of Himself] for sins for all time, SAT DOWN [signifying the completion of atonement for sin] AT THE RIGHT HAND OF GOD [the position of honor]