How do we know Christ's sacrifice was for the elect?

The affirmation that Christ's sacrifice is particularly for His elect finds strong support in the high priestly prayer of Jesus in John 17. In verse 9, Jesus says, 'I pray for them: I pray not for the world, but for them which thou hast given me; for they are thine.' This demonstrates that His intercession is exclusive for those whom God has given Him. Such a distinction emphasizes the nature of Christ's atonement: it is effectual for those whom the Father has chosen and represents God's sovereign grace in salvation. Understanding this helps believers recognize the depth of Christ's love for His own and ensures that His sacrifice is sufficient for their justification.