This is the second single from comedian Eddie Murphy's 9 album, his first musical record since 1993's Love's Alright. He told the story of the song to Billboard magazine: "'Promise' started with me just playing the little guitar licks for about a month. Trent [Gumbs], who helped me produce the album was like 'You should write something to that.' Then that first line popped out. Sometimes it comes out all at once, and other times just in pieces."
"Sloop John B" is a traditional West Indian folk song, and it was a huge hit for The Beach Boys in 1966. They tweaked the lyric, "This is the worst trip since I've been born" to "...I've ever been on" as a wink to acid culture.