"I Don't Know How to Love Him" is a song from the 1970 rock opera Jesus Christ Superstar written by Andrew Lloyd Webber (music) and Tim Rice (lyrics), a torch ballad sung by the character of Mary Magdalene. In the opera she is presented as bearing an unrequited love for the title character. The song has been much recorded, with "I Don't Know How to Love Him" being one of the rare songs to have had two concurrent recordings reach the Top 40 of the Hot 100 chart in Billboard magazine, specifically those by Helen Reddy and Yvonne Elliman, since the 1950s when multi-version chartings were common.

"I Don't Know How to Love Him" had originally been published with different lyrics in the autumn of 1967, the original title being "Kansas Morning". The melody's main theme has come under some scrutiny for being non-original, being compared to a theme from Mendelssohn's Violin Concerto in E Minor. In December 1969 and January 1970, when Andrew Lloyd Webber and Tim Rice completed Jesus Christ Superstar, Rice wrote new lyrics to the tune of "Kansas Morning" to provide the solo number for the character of Mary Magdalene (Rice and Webber's agent David Land would purchase the rights to "Kansas Morning" back from Southern Music for £50). Now entitled "I Don't Know How to Love Him", the song was recorded by Yvonne Elliman and completed between March and July 1970. When first presented with "I Don't Know How to Love Him", Elliman had been puzzled by the romantic nature of the lyrics, as she had been under the impression that the Mary she'd been recruited to portray was Jesus's mother.

Recorded in one take at Olympic Studios in June 1970, "I Don't Know How to Love Him" has been universally acclaimed as the high point of the Jesus Christ Superstar soundtrack since the album's September 1970 release; in 2003 The Rough Guide to Cult Pop would assess Elliman's performance: "It's rare to hear a singer combine such power and purity of tone in one song, and none of the famous singers who have covered this ballad since have come close."

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