Alan Shepard was the American astronaut, businessman, test pilot and naval aviator. In 1961, he became the first person to visit the space and in 1971, he walked on the moon.
Supposedly, when Shepard (who was known as a bit of a joker) gave Bob Hope a tour of a NASA facility in the early 1960s, Hope joked about hitting a ball on the moon. The idea stuck with Shepard, since one of the things the astronauts had been expected to do from the very beginning was act as science ambassadors to the general public.
So he figured out how he could do it, then he went to talk to NASA director, Bob Gilruth. At first, Gilruth was adamantly opposed. But Shepard explained what he wanted to do and how, and promised to wait until the very end of lunar exploration, and only proceed if the mission had gone flawlessly, so as to avoid any possibility of embarrassing the agency.
Check this official interview.
Wikipedia - Alan Shepard
Check this video footage released by the officials. https://youtu.be/t_jYOubJmfM