Something is lacking in all writing. You can never be sure how the written page will affect the reader, because his mood, his circumstances, his affections are so changeable. It is different with the spoken word. If it is harsh and ill-timed it can always be remodeled.
 Martin Luther, Commentary on the Epistle to the Galatians (1535). copy citation

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Author Martin Luther
Source Commentary on the Epistle to the Galatians
Topic writing mood
Date 1535
Language English
Reference
Note Translated by Theodore Graebner
Weblink http://www.gutenberg.org/files/1549/1549-h/1549-h.htm

Context

“The false apostles had torn the form of Christ out of the hearts of the Galatians and substituted their own form. Paul endeavors to reform them, or rather reform Christ in them.
VERSE 20. I desire to be present with you now, and to change my voice.
A common saying has it that a letter is a dead messenger. Something is lacking in all writing. You can never be sure how the written page will affect the reader, because his mood, his circumstances, his affections are so changeable. It is different with the spoken word. If it is harsh and ill-timed it can always be remodeled. No wonder the Apostle expresses the wish that he could speak to the Galatians in person. He could change his voice according to their attitude. If he saw that they were repentant he could soften the tone of his voice.” source