This is taken from the Beatles listing, it was written by: Phantom_spaceman; Ashley Chittock; and,Dave Howell

This song was written by John Lennon in India while they were studying Transcendental Meditation under Maharishi Mahesh Yogi. One of their friends, Prudence Farrow (Mia Farrow’s sister), became overzealous in her meditation and turned into a recluse. Lennon wrote this song as a message to snap her out of it. Said Lennon in a 1980 Playboy interview:

She was trying to find God quicker than anyone else. That was the competition in Maharishi’s camp: who was going to get cosmic first.

Prudence Farrow herself described the state she put herself into in a 2015 Rolling Stone interview:

I had been [meditating for] five days straight. I hadn’t gone to the bathroom, I hadn’t slept, and I hadn’t eaten… The older people on the course, they were sleeping; they were sunbathing on top of the roof; they would go for walks. I was one of many [who were] just maybe a little more extreme because I had no parental controls on me, so I could go all the way.
Right from the start, all I cared about was getting the job done, clearing out whatever darkness I had inside me, and becoming healthy and being able to live a real life. I knew meditation could do it for me — I didn’t understand how.

Prudence first heard the song through her mother – she had a copy of the White Album at her apartment and used her reaction to the song to win a game of “killer”. Prudence has since gone on to call the song “…very beautiful… very positive [and] an important song.”

For more annotations visit The Beatles version:

The Beatles - Dear Prudence — Genius

Dear Prudence Lyrics: Dear Prudence, won't you come out to play / Dear Prudence, greet the brand new day / The sun is up, the sky is blue / It's beautiful and so are you / Dear Prudence won't you come