“You can’t spell painting without pain” is a saying that has been printed on several images. The saying means that a painter’s struggles are produced in a painting. Also, painting can be physically (as well as mentally) demanding.
   
On the American television sitcom 3rd Rock from the Sun, the episode “The Art of the Dick” that was written by Bob Kushell and originally aired on March 19, 1996,  Dick Solomon (actor John Lithgow) said:
   
“But don’t forget, out of suffering comes creativity. You can’t spell ‘painting’ without ‘pain.’”
 
“You can’t spell paint without pain” is a variation of the saying.
   
       
Wikipedia: 3rd Rock from the Sun
3rd Rock from the Sun is an American sitcom that aired from 1996 to 2001 on NBC. The show is about four extraterrestrials who are on an expedition to Earth, which they consider to be a very insignificant planet. The extraterrestrials pose as a human family to observe the behavior of human beings.
 
IMDb (The Internet Movie Database)       
3rd Rock from the Sun (1996–2001)
The Art of Dick
TV-PG | 22min | Comedy, Family, Sci-Fi | Episode aired 19 March 1996
 
Springfield! Springfield!
3rd Rock from the Sun e01s11
Episode Script
The Art of the Dick
(...)
But don’t forget, out of suffering comes creativity. You can’t spell “painting” without “pain.”
 
5 January 1997, The Sun-Herald (Sydney, Australia), “Off the Air,” Now sec., pg. 3, col. 4:
“Out of suffering comes art—you can’t spell painting without pain!”
—Dr Albright struggles with his artistic leanings, 3rd Rock From The Sun
 
Google Groups: alt.tv.3rd-rock
Season?
Warren Peace
11/29/99
(...)
Mary: ‘You can’t spell painting without pain.’
Harry: ‘Or ting.’
     
27 December 2006, The Guardian (London, UK), “Football: Clogger A sideways glance at football,” pg. 4:
Never despair, mate. Out of difficulty comes creativity. You can’t spell painting without pain.
 
Twitter
Shelby Collinge
@ShelbyCollinge
‘Out of suffering comes creativity.  You cannot spell painting without pain.’—John Lithgow
1:44 PM - 9 Mar 2009
 
Google Books
The Key Journey to Success:
Thinking Ahead Will Get You Ahead
By Arnaud Romeo Noume
Xlibris Corporation (Xlibris.com)
2011
Pg. 18:
John Lithgow in Third Rock From the Sun:
Out of suffering comes creativity. You cannot spell painting without pain.
       
OregonLive
January 31, 2018
Before you paint, take time to pick, sample and test colors: The Pecks 
By Marcia and Dennis Peck, For The Oregonian/OregonLive
Am I the only one who noticed you can’t spell “painting” without “pain”?
 
And in this case, we’re talking about actual physical pain.
 
Turns out, Marcia wrenched something in her back while doing the painting for this column.
     
YouTube
You can’t spell painting without pain! (That joke was cheesy)
Drawing Freaks
Published on Jul 25, 2018
I did a painting yaay and it took hours even back pain but all worth it
 
Twitter
inspiration tweet
@PirationIns
Out of suffering comes creativity. You cannot spell painting without pain. -John Lithgow in Third Rock From the Sun ##InspirationalTweet
4:29 AM - 27 Jun 2019