I quite randomly stumbled upon this quotation from Lutheran theologian Hermann Sasse*, the anti-Nazi activist who settled in Australia. Paul McCain nailed it to the door at First Things eight years ago.
Nota bene: By “evangelical,” Sasse is using the European terminology for what we would call Lutheran. See the explanation at this post.
From Hermann Sasse, Here We Stand, pp. 110-111:
“Lutheran theology differs from Reformed theology in that it lays great emphasis on the fact that the evangelical church is none other than the medieval Catholic Church purged of certain heresies and abuses. The Lutheran theologian acknowledges that he belongs to the same visible church to which Thomas Aquinas and Bernard of Clairvaux, Augustine and Tertullian, Athanasius and Ireneaus once belonged. The orthodox evangelical church is the legitimate continuation of the medieval Catholic Church, not the church of the Council of Trent and the [First] Vatican Council which renounced evangelical truth when it rejected the Reformation. For the orthodox evangelical church is really identical with the orthodox Catholic Church of all times. And just as the very nature of the Reformed Church emphasizes its strong opposition to the medieval church, so the very nature of the Lutheran Church requires it to go to the farthest possible limit in its insistence on its solidarity and identity with the Catholic Church. It was no mere ecclesiastico-political diplomacy which dictated the emphatic assertion in the Augsburg Confession that the teachings of the Evangelicals were identical with those of the orthodox Catholic Church of all ages, and no more was it romanticism or false conservatism which made our church anxious to retain as much of the old canonical law as possible, and to cling tenaciously to the old forms of worship.”