Woo! A semi-fixed set of readings! Easter 2 is always Doubting Thomas Sunday, regardless of cycle. Although the rest of the readings do change, so that gives us a chance to let scripture interpret scripture in different ways each time.

1 Peter 1:3-9

…who are being protected by the power of God through faith for a salvation ready to be revealed in the last time.
— 1 Peter 1:5 (NRSVue)
…or you are receiving the outcome of your faith, the salvation of your souls.
— 1 Peter 1:9 (NRSVue)

Verses 5 and 9 are quoted together in Formula of Concord, Solid Declaration, Article 4: Good Works (FC, SD 4.34) as the end of a series of quotes from Paul showing that faith does not simply grant access to God's gift, but carries us all the way through life and into God's gift of salvation.

John 20:19-31

Jesus said to them again, “Peace be with you. As the Father has sent me, so I send you.” When he had said this, he breathed on them and said to them, “Receive the Holy Spirit. If you forgive the sins of any, they are forgiven them; if you retain the sins of any, they are retained.”
— John 20:21-23 (NRSVue)

Verses 21 thru 23 are quoted in The Augsburg Confession, Article 28: Concerning the Power of Bishops/Concerning the Church's Power (AC 28.6) to clarify the teaching of the reformers about what said "power" is—namely "to preach the gospel, to forgive or retain sin, and to administer and distribute the sacraments" (AC 28.5).

Verse 21 is quoted twice in Treatise on the Power and Primacy of the Pope (Tr 9, 31) to make two different points. The first citation is to show that Jesus did not create a hierarchy among the apostles, so the office of Pope does not have any ordained primacy. The second citation, with several other scriptural references, makes the argument that those who hold positions of authority in the church do not have God's authorization to civil authority and enforcement.

Verse 23 comes up in a smattering of places. First in a footnote in Smalcald Articles, Part 3, Article 7 (SA 3.7.1, n. 140) showing that Jesus gave the church authority to bind and loose sins. This verse is quoted in Treatise on the Power and Primacy of the Pope (Tr 23) to show that Jesus gave all the apostles authority to bind and loose sins. Finally, this verse is cited in a footnote in Small Catechism, Baptism, Short Order of Confession (SC 4.29, n. 95) as a scriptural citation for the command of Jesus by which forgiveness is pronounced.

TheoThru

Authority is always a tricky subject. Claims to authority become even more of an issue when paired with doubt. This set of readings is a helpful reminder (as always) of the scope of God's call to the institution of the church: to preach the gospel, to forgive or retain sins, and do administer the sacraments. By returning to John 20:23 consistently, we can see a complicated relationship between ecclesiastical authority and civil authority. If we loose sight of God's activity in both the church and in government, doubt becomes a central motivation for unhelpful actions. And yet, some measure of having to see authority act well is necessary.

How does the institution of the church faithfully call out civil authority when they need to be forgiven or actively not forgiven?
How does the institution of the church, and the people who are the church, respond when we are called out by civil authority as needing to ask for forgiveness?
When is it necessary to expect to see change before forgiveness is granted?