For by one offering [sacrifice] He has perfected forever those who are being sanctified. (Hebrews 10:14)
In this verse, we have two tenses, and both are significant. The first one is called the perfect tense: “for by one offering [sacrifice] He has perfected forever….” You can say the sacrifice is perfectly perfect. It is completely complete. Just before this phrase, the writer of Hebrews said that the Old Testament priests always stood, offering again and again the same sacrifices that could never take away sin. Then, the writer said about Jesus, “But this Man, after He had offered one sacrifice for sins forever, sat down at the right hand of God” (Hebrews 10:12). Notice the contrast between the Old Testament priests, who stood, and Jesus, who offered His sacrifice and sat down. Why did Jesus sit down? Because He had nothing left to do. He had done it all. Whereas the job of the Old Testament priests was never finished because their sacrifices were not adequate to deal with the real problem, Jesus’ death on the cross was a complete and final act.
As far as what Jesus has done, it is complete and perfect. Nothing must be added to it, and nothing can ever be taken away from it. Jesus’ sacrifice is valid forever. That is the perfect tense.
Then, speaking about those of us who are appropriating Jesus’ sacrifice, the author of Hebrews wrote, “He has perfected forever those who are being sanctified” (Hebrews 10:14). “Are being sanctified” is in the present progressive tense. What Jesus has done is perfect, and our appropriation of it is continual, ongoing. As we are sanctified, as we are set apart to God more and more, and as we draw closer to God and appropriate more of God’s provision and promises, we are entering more and more into the provision of the sacrifice.