Johann Spangenberg (1484–1550), a Lutheran pastor, authored one of the best selling postils1 of the sixteenth century, the Postilla Teütsch, which helped to prepare children to understand the lectionary readings.

In this post on Luke 5:1-11 for the Fifth Sunday after Trinity, Spangenberg asserts that Christ’s words penetrated the hearts of the disciples—not merely their ears—empowering them to heed his call.

Commentary on Luke 5:1-11

What does Jesus say to him? “Do not be afraid, from now on you will catch people.” With these words, Christ leads these disciples from fear to joy, from hell to heaven, from condemnation into eternal life.

It is as if he said: “Dear Simon, you shall not die because of your sins, nor shall you be condemned. You shall live a long life and become a fisher, not of fish but of people. And not you alone, but the others with you. I will not only absolve all of you from your sins, but I will also give you the power to absolve the sins of others.”

And what did Peter, Andrew, John, and James do when they heard these words? They brought the ship to land and, leaving everything, followed after him. And how was God’s word so powerful? Christ did not of course only speak to them in their ears but also in their hearts. To leave father and mother, house and hearth, and everything on account of God is not such a small work that a person could do it all on his own. It is a work of the Holy Spirit.

But we know that the word of Christ is spirit and life, so it is good to believe that the calling of the apostles did not only come into their ears but also into their hearts; otherwise they would not have given up father and mother and everything else so quickly and followed Christ.

Luke, ed. Beth Kreitzer, Reformation Commentary on Scripture, NT Vol. III, p. 114

1 “A postil or postill (Latin: postilla; German: Postille) was originally a term for Bible commentaries. It is derived from the Latin “post illa verba textus” (after these words), referring to Biblical readings.” Postil – Wikipedia, the free encyclopedia