How do we know Christ's sacrificial atonement is sufficient?

The sufficiency of Christ's atonement is anchored in God's own declaration of satisfaction with His sacrifice. As stated in 2 Corinthians 5:21, 'For He made Him who knew no sin to be sin for us, that we might become the righteousness of God in Him.' This means that Christ's perfect obedience and subsequent sacrifice fulfilled the necessary justice for our sins, thus providing a perfect way toward salvation—no further sacrifices or works are needed. Our faith rests on His completed work, illustrating that He has made our way perfect.