The anonymous road artist from Bristol generated the functions for his resort at Bethlehem, known as The Walled Away Hotel, which includes a gallery and museum.
Earning nearly double the estimated figure, Banksy's painting titled Mediterranean Sea View 2017 highlight the European refugee crisis which saw several people trying to reach the continent across the Mediterranean and Aegean seas after fleeing war and conflict and embarking on risky journeys.
Tens of thousands are thought to have died as European countries on the Mediterranean and Aegean Seas turned away people fleeing violent conflicts across North Africa and the Middle East.
Proceeds will go to the construction of new offices for the treatment of acute strokes and the purchase of children's rehabilitation equipment to the hospital in Bethlehem.
"Though posing as eighteenth or nineteenth-century paintings of the "Natural Sublime", the present work undermines and subverts the viewer's expectations to broach a hard contemporary issue", the auction house added.
"Apple is the world's most profitable company. and it only exists because they allowed in a young man from Homs".
The trio of paintings were initially expected to fetch £1.2m when they appeared in Sotheby's Rembrandt to Richter evening sale.
The paintings sold for 2.9 million dollars at a London auction on Tuesday.
The England-based artist has addressed the migrant crisis in numerous works, including a 2016 portrait of Apple's late founder and CEO Steve Jobs holding an original Apple computer in one hand and a black sack thrown over his shoulder in the other. We hope that we have succeeded by giving you the full details and information.