The LCMS teaches that all humanity, with the sole exception of Jesus Christ, is born in sin and guilt as a result of Adam's transgression. Original sin is not merely a tendency toward sin or a consequence of Adam's bad example; rather, his sin is imputed to all his descendants, and all are born stained with guilt and corruption.

Total depravity is affirmed: in the state of nature, before conversion, the human will is bound and enslaved to sin. The human being cannot, by his own power, turn to God, believe the gospel, or perform any good work pleasing to God. The will is not merely weakened by sin but is entirely incapable of spiritual good apart from the regenerating work of the Holy Spirit. This is why the atonement is necessary and why the gospel must be proclaimed and the Spirit must work faith through means of grace.

Infants are born in original sin and guilt; they are not innocent. However, LCMS teaches that infants also stand under the benefits of Christ's universal atonement and can be regenerated through baptism. Unbaptized infants who die are entrusted to God's mercy; the LCMS does not teach that they are automatically damned, but this matter is left to God's judgment.