“Πέτρος (Peter), and πέτρᾳ (rock)” Matthew 16:13–20
Old Testament Isaiah 51:1–6
Introit Psalms 2:6-7; 117; antiphon: Psalm 115:18
Epistle Romans 11:33–12:8
Gospel Matthew 16:13–20
Lutheran Service Book Three Year Lectionary (Bellingham, WA: Concordia Publishing House, 2009).
Third Article of the Apostles Creed:
I believe in the Holy Spirit, the holy Christian church, the communion of saints, the forgiveness of sins, the resurrection of the body, and the life everlasting. Amen.
What does this mean?
I believe that I cannot by my own reason or strength believe in Jesus Christ, my Lord, or come to Him; but the Holy Spirit has called me by the Gospel, enlightened me with His gifts, sanctified and kept me in the true faith. In the same way He calls, gathers, enlightens, and sanctifies the whole Christian church on earth, and keeps it with Jesus Christ in the one true faith. In this Christian church He daily and richly forgives all my sins and the sins of all believers. On the Last Day He will raise me and all the dead, and give eternal life to me and all believers in Christ. This is most certainly true. 1
 Luther, Luther’s Small Catechism with Explanation (St. Louis, MO: Concordia Publishing House, 2017), 17–18.