Collect: Merciful and eternal God, Your holy apostles Peter and Paul received grace and strength to lay down their lives for the sake of Your Son. Strengthen us by Your Holy Spirit that we may confess Your truth and at all times be ready to lay down our lives for Him who laid down His life for us, even Jesus Christ our Lord, who lives and reigns with You and the Holy Spirit, one God, now and forever.
Readings: Acts 15:1-21 / Galatians 2:1-10 / Matthew 16:13-19
Preface: It is truly good, right, and salutary that we should at all times and in all places give thanks to You, holy Lord, almighty Father, everlasting God, for You have mightily governed and protected Your holy Church, in which the blessed Apostles and Evangelists proclaimed Your divine and saving Gospel. Therefore with Patriarchs and Prophets, Apostles and Evangelists, with Your servants Peter and Paul, and all the company of heaven, we laud and magnify Your glorious name, evermore praising You and saying... (LSB)
Then Christ said: And I say to you that you are Peter and on this rock I will build my Church. On this rock I will build the faith that you now confess, and on your words: You are the Christ, the Son of the living God, I will build my Church. For you are Peter, and the name Peter comes from petra, the word for "rock" and not vice versa. "Peter" therefore comes from petra, just as "Christian" comes from Christ. - St. Augustine, Homily for this day