Little men would be discouraged if they could see themselves in their true light. So conceit was sent into the world — God’s great gift to little men.
Bruce Barton (1886-1967) American author, advertising executive, politician
“The Gift to Little Men” (1926)
(Source)
Often paraphrased, "Conceit is God's gift to little men."
Quotations by:
Barton, Bruce
Fortunate are those who recognize the divine importance of youth’s cocksureness and conceit, and yet know how, gently and appreciatively, to temper it with the riper judgment of added years.
Bruce Barton (1886-1967) American author, advertising executive, politician
More Power to You, ch. 27 (1917)
(Source)
But to every man of vision the clear Voice speaks; there is no great leadership where there is not a mystic. Nothing splendid has ever been achieved except by those who dared believe that something inside them was superior to circumstance.
Bruce Barton (1886-1967) American author, advertising executive, politician
The Man and the Book Nobody Knows, ch. 1 “The Executive” (1924)
(Source)
When you are through changing, you are through.
Bruce Barton (1886-1967) American author, advertising executive, politician
Article Title, The American Magazine (1929?)
(Source)
Barton was a regular contributor to The American Magazine. Both the cited source (from 1929) and this suggest this was an article he contributed no later than 1929.
The saying has been misattributed to a number of more recent consultants, motivational speakers, etc.