How do we know that Christ's sacrifice is effectual?

The effectuality of Christ's sacrifice is grounded in the belief that it accomplished redemption for God's chosen people. Unlike the belief that Christ's blood made salvation merely possible, the historic Reformed view understands that His sacrifice secured salvation definitively. Jesus' suffering and the shed blood were sufficient for the salvation of everyone God has chosen. In Isaiah's prophecy, God's word always accomplishes its intended purpose; thus, Christ, as the embodiment of God's word, also fulfills His mission without fail.