[13] Penitential works.

[14] Cf. Acts 2:46.

[15] See Vol. I, p. 310.

[16] In the Vulgate the Greek word "mystery" is translated by sacramentum. See below, p. 258.

[17] Luther still adheres to the doctrine of transubstantiation. But see below, pp. 187 ff.

[18] See p. 11.

[19] Cf. below, p. 192.

[20] See Luther's explanation of the First Commandment in the Catechisms. Also the answer to the last question in Part V, Small Catechism.

[21] Treatise on Penance (Weimer Ed., II, 721), where Luther exhorts the troubled conscience to pray with the father of the lunatic boy, "Lord, I believe, help Thou mine unbelief," and with the Apostles, "Lord, increase our faith."

[22] Cf. above, p. 17.