Jesus says that His blood is poured out for “many,” not for “all” (Matt. 26:28). His death is not effectual for all people who have ever lived; Christ’s death is effectual only for His people, securing eternal salvation for all those who trust in the promises of God through Him. Because He has made an atonement for all those in Him, our pursuit of holiness is not in vain, for Christ is transforming us into His image as we work out our salvation (Phil. 2:12–13).
For further study:
The Bible in a year: