When an official, a servant, a teacher minds his business and performs his duty faithfully without concerning himself about matters that are not in his line he may rejoice in himself.
 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 duty business
Date 1535
Language English
Reference
Note Translated by Theodore Graebner
Weblink http://www.gutenberg.org/files/1549/1549-h/1549-h.htm

Context

“To preach the Gospel for praise is bad business especially when people stop praising you. Find your praise in the testimony of a good conscience.
This passage may also be applied to other work besides the ministry. When an official, a servant, a teacher minds his business and performs his duty faithfully without concerning himself about matters that are not in his line he may rejoice in himself. The best commendation of any work is to know that one has done the work that God has given him well and that God is pleased with his effort.
VERSE 5. Every man shall bear his own burden.
That means: For anybody to covet praise is foolish because the praise of men will be of no help to you in the hour of death.” source