Works cannot save us. Seems like we have to keep repeating this, but at least the repetition is biblical.

Psalm 43

Vindicate me, O God, and defend my cause
against an ungodly people;
from those who are deceitful and unjust
deliver me!
— Psalm 43:1

Verse 1 is quoted by Melanchthon in the Apology of the Augsburg Confession, Article 4: Justification (AP 4.180C) as part of an extensive list of scriptural citations that show it is faith that justifies us before God, not our works. Good works that please God are a fruit of faith. A conscience that knows it’s own sin will be terrified before God if justification is through works. How could you ever be sure you’ve done enough?

Matthew 23:1-12

[Jesus said,] “The scribes and the Pharisees sit on Moses’ seat; therefore, do whatever they teach you and follow it; but do not do as they do, for they do not practice what they teach.”
— Matthew 23;2-3

Verses 2 thru 3 or verse 2 is cited in The Augsburg Confession, Article 8: What Is the Church (AC 8.2, verses 2-3 in the German, verse 2 in the Latin). This line from Jesus shows that not everyone who calls themself Christian, not everyone who goes to church, not everyone who is ordained as part of the institution of the church is part of the invisible Church. This is also, then, the answer to the Donatist heresy—one of the placed the Lutheran reformers agreed with Rome.

Melanchthon cited verse 3 in the Apology of the Augsburg Confession, Article 28: Ecclesiastical Power (AP 28.21) because the Confutation used this verse to support the authority of the pope. Even if the pope is wicked, what he teaches should be followed, the argument went. To which Melanchthon wrote: “To the extent that they teach wicked thins they should not be heard,” citing Acts 5:29—that we should obey God and not mortals. The wicked teachings were forcing the requirement of made up devotional practices or acts of worship and teaching that they must be followed in order to be forgiven.

[Jesus said of the Pharisees,] “They do all their deeds to be seen by others; for they make their phylacteries broad and their fringes long.”
— Matthew 23:5

Verse 5 is cited in a footnote to The Large Catechism, Part 1: The Ten Commandments, Conclusion (LC 1.331, n. 131) as a reminder that we should keep the Commandments before us not as a kind of showy piety—the phylacteries and fringes of the priestly garments—but in order to remind us of who God wants us to live and form us with reverence to God.

TheoThru

Works cannot justify us before God. If we look at a person’s works to judge them faithful or not, we might be confusing what is visible with what is invisible. This forces us to wrestle with our understanding of who God is and why God gave us the Commandments.

Are the Commandments mostly punitive or guidance?
Is God the one who punishes or the one who forgives?
How do we move beyond these dichotomies to discover the depth of God’s love that provides both structure and encouragement?