An Irish blessing has been printed on several images:
 
“May your pockets be heavy and your heart be light.
May good luck pursue you each morning and night.”
 
The origin of the saying is unknown; this version has been cited in print since at least 1999. “May your pockets be heavy and your heart be light and may God’s grace be with you each day and each night” was cited in a 1986 newspaper.
 
“May your heart be light and happy, may your smile be big and wide, and may your pockets always have a coin or two inside!” is a related blessing.
   
   
Newspapers.com
16 March 1986, The Journal News (White Plains, NY), Suburban People, pg. 19, col. 2:
BROTHER JOHN G. DRISCOLL
President, Iona College, New Rochelle
Five Irish wishes for St. Patrick’s Day:
(..)
“May your pockets be heavy and your heart be light and may God’s grace be with you each day and each night.”
   
Google Books
Irish Blessings
Bath: Parragon
1999
Pg. 16:
May your pockets be heavy and your heart be light.
May good luck pursue you each morning and night.
 
Google Groups: alt.support.depression
My Holiday Greetings to ASD (sp. long)
Mary Beth McE
12/24/99
(...)
May your pockets be heavy and your heart be light,
May good luck pursue you each morning and night.
 
17 March 2000, Daily Herald (Arlington Heights, IL), “St. Pat’s Day brings folks to bakery” by Shawn & Laura Ehrke, pg.. 4:
“May your pockets be heavy and your heart be light,
May good luck pursue you day and night.”
-Anonymous
 
Google Books
The Encyclopedia of Greeting Card Tools & Techniques
By Susan Pickering Rothamel
New York, NY: Lark Books
2008
Pg. 279:
May your pockets be heavy and your heart be light,
may good luck pursue you each morning and night. —Irish Blessing
 
Twitter
That guy in Denver‏
@Watrfrnt
May your pockets be heavy and your heart be light, may good luck pursue you each morning and night. - Irish saying
9:56 AM - 17 Mar 2008
   
Google Books
Connecting in the Land of Dementia:
Creative Activities to Explore Together
By Deborah Shouse
Las Vegas, NV: Central Recovery Press
2016
Pg. ?:
“May your pockets be heavy and your heart be light. May good luck pursue you each morning and night.”—Irish Blessing