The husband of Queen Elizabeth II -- and the longest-serving consort of a British monarch -- died April 9 at the age of 99. Philip, also known as the Duke of Edinburgh, was married to the queen for 73 years.
His funeral took place Saturday at Windsor Castle. Only 30 members of the royal family were permitted to attend the service due to coronavirus pandemic regulations.
"Rest in peace HRH Prince Philip, finished this off whilst listening to your life what a great legacy left behind," Payne, 27, wrote alongside a photo of the painting.
It has gotten more than 1.3 million "likes."
He also shared on Instagram Stories images of the portrait as it was in progress.