The song received generally mixed reviews from contemporary music critics. "When You Believe" experienced moderate success on the US Billboard charts, peaking at only number fifteen on the Hot 100, despite heavy media attention and live promotion. The song however, achieved strong charting throughout Europe and other worldwide regions, peaking within the top five in Belgium, France, Italy, The Netherlands, Norway, Spain, Sweden, Switzerland and the United Kingdom. Due to strong single sales in Europe and the US, the song has received various certification awards throughout many major music markets.
"When You Believe" was awarded the Academy Award for Best Original Song at the 71st annual ceremony on March 21, 1999. Prior to their performance of the song that night, Schwartz left Babyface's name off the nomination submission sheet. He felt that because the additions Babyface added to the song were not featured in the actual film version, he did not deserve writing credits. However, while Babyface did not receive the Oscar, Carey and Houston performed his version of the song, because they were more familiar with it than the one in the film. Prior to their performance at the Academy Awards, they sang it on November 26, 1998 on The Oprah Winfrey Show, promoting the song, as well as both their albums.
The song featured two music videos. The first and most commonly seen video was filmed at Brooklyn Academy of Music performing arts center. The video features both singers, and begins with Houston and Carey performing in a large auditorium, giving the illusion of a concert. Towards the end of the video, clips of the film are projected onto a large screen at the concert, while they belt out the final verse. The alternate video was only released on NBC's special, When You Believe: Music Inspired by the Prince of Egypt, broadcast on December 13, 1998. It features a similar synopsis, with both singers performing on a large stage of an old Egyptian pyramid. The main difference however, is the fact that no film clips are played in the video and there is no audience present.
It's sort of a message song. It's what 'Prince of Egypt' is about, Moses. If we were ever going to come together on any kind of record, this is definitely the right one, and really the coolest thing to me is that after all of the drama and everybody making it like we had a rivalry, she was just really cool and we had a really good time in the studio. We had fun. And so, if nothing else, it was a good experience... and diva-ism, whatever."
—Carey, on working with Houston in the studio, during an interview with Vibe.
When Carey compiled her first compilation effort #1's, "When You Believe" was included in the track listing. According to Carey, the song was included because she felt it was "a miracle" that she and Houston collaborated on a record. During the development of All That Glitters (a film Carey was working on at the time, later known as Glitter), she had been introduced to DreamWorks co-owner Jeffrey Katzenberg, who asked her if she would record the song "When You Believe" for the soundtrack of the animated film The Prince of Egypt. Houston, on the other hand, was introduced to the project though Kenneth "Babyface" Edmonds, with whom she had been collaborating on her album at the time, My Love Is Your Love. After they were shown the film separately, both became very enthusiastic about participating in the project.
The song was co-written by Stephen Schwartz and Babyface, who also produced the song. Carey had previously collaborated with Babyface on her albums, Music Box (1993) and Daydream (1995), and Houston had previously collaborated with him on her album I'm Your Baby Tonight (1990), as well as her song "Queen of the Night" from The Bodyguard: Original Soundtrack Album (1992), her tracks on the Waiting to Exhale soundtrack (1995) and two tracks from The Preacher's Wife soundtrack (1996), "You Were Loved" and "My Heart Is Calling". Babyface expressed how he went through more than one version of the song and described its production as a beautiful movie ballad, something different from anything he, Carey or Houston had ever previously recorded. In an interview with Vibe, Carey said that she "liked [the song] the way it was". She had characterised it as "a very big ballad but in an inspirational way" and denied speculation that there had been past rivalry or animosity between her and Houston prior to its recording: "I never even really talked to her until this. We never had any issues between us. The media and everybody made it an issue." In an interview with Ebony, Houston spoke about her relationship with Carey:
"I enjoyed working with her very much. Mariah and I got along very great. We had never talked and never sang together before. We just had a chance for camaraderie, singer-to-singer, artist-to-artist, that kind of thing. We just laughed and talked and laughed and talked and sang in between that ... It's good to know that two ladies of soul can still be friends. We talked about doing other things together, enterprise-wise, which is cool, because she's got a good, vivid mind, that girl. She's a smart lady. I really like Mariah."
While the pair continued to express their positive feelings for one another, tabloids began writing the opposite. There were claims that the two bore ill will against each other, and that they had to record the song separately due to constant tension. While media speculation grew as the film's release date drew near, both singers maintained that they had become close friends, and had only the most positive things to say about each other. Originally, Schwartz composed the film version of "When You Believe", which was sung in the film by the characters of Tzipporah (Michelle Pfeiffer) and Miriam (Sally Dworsky). It featured some different instrumentation from the original, and used a children's choir as well as some lines in Hebrew. However, in order to give the song a wider radio and pop appeal, Edmonds changed some of the song's instrumentals and replaced the children's choir with a gospel one. His version was considered more "commercial" and would make the song "help sell the movie". Schwartz's original version was titled "When You Believe", while Edmonds' enhanced version was titled "The Prince of Egypt (When You Believe)".
The Prince of Egypt is an adaptation of the Biblical story of the Exodus. "When You Believe" is sung in the film by characters Tzipporah and Miriam, and a chorus of people departing from the slavery of Egypt to the Red Sea and the Promised Land. The protagonists of this ballad recall tough times that have caused them to question their own faith: they have prayed for many nights to God, but those prayers have seemed to remain unanswered, and now they wonder if their faith has been only a waste of time. Nevertheless, the main characters realize that although the times may be difficult, their faith should remain strong. The original draft of the song used the lyric "you can do miracles when you believe", but this seemed to imply that the believer, not God, was responsible for performing miracles; the lyric was later changed to "there can be miracles when you believe".
Houston had sung in a church choir while growing up, and Carey had always connected to her faith through music, especially during any difficult times. This song became one of the many reasons that both singers were so interested in the project. They each felt that spreading faith in God was an important and honorable aspect of their career. While describing the song's lyrics and message, Houston said the following in an interview with 'Ebony:
A powerful ballad; [songwriter] Stephen Schwartz is a genius. You have to be a child of God to understand the depth of this song. Mariah and I did it as we felt it. We both felt very connected to the song because of our background. What can I say? (It is) Just a beautiful song. What a lyric! I can't talk about it--just listen to it.
"When You Believe" is a slow tempo ballad, which incorporates pop and contemporary R&B genres. Carey and Houston's parts in the song are written in different keys, both musically and vocally. During the last bridge and chorus, gospel inspired background singers join the song, giving it a "layered sound" while Carey and Houston's voice switch off belting the bridge. After "When You Believe" was written, Babyface added additional instrumentation, as well as a final bridge. The song is set in signature common time. Houston's verses and chorus are written in the key of B minor and features a basic chord progression of A♭-G♭1. Her vocals in the song range from the note of F♯3 to F♯5. Carey's chorus are set in the higher key of E major and is set in common time as well. Her vocal range in the song spans from the low note of G3 to the high note of G6, spanning more octaves than Houston's voice in the song. The song climaxes rise to the last chorus which is set even higher in the key of F-sharp major. Steve Jones from USA Today called the song a "soaring duet" and felt that the song would be able to appeal to many types of listeners and "cross all genres."
"When You Believe" received a mixed review from David Browne, an editor from Entertainment Weekly. He gave it a C-, and wrote "[the song has] so much sap, maple trees will be jealous." He called the song's religious aspect "insipid" and felt its inspirational message felt forced and generic. While Stephen Thomas Erlewine of Allmusic was reviewing Prince Of Egypt OST, he called this duet "unexpected -- and unexpectedly dull." Paul Verna of Billboard called this song "high-powered" duet instead. When Billboad reviewed Houston's album they highlighted it.
The song performed moderately in Australia, where it entered at number 25 on the ARIA Singles Chart during the week of December 6, 1998. It remained on the chart for 14 weeks, spending its last week on the chart at number 50; it was certified gold by the Australian Recording Industry Association (ARIA), denoting shipments of over 35,000 units. In New Zealand, it peaked at number eight on the singles chart, and spent nine weeks fluctuating in the singles chart. "When You Believe" experienced its highest charting in Europe. In Belgium, it reached number five on the Flanders Ultratop 50, and peaked at number four and spent 20 weeks on the Wallonian Ultratop 40. During the week of December 5, 1998, "When You Believe" entered the Dutch Top 40 at number fifty-four. The song spent twenty-one weeks on the singles chart and was peaked at number four. Due to strong single sales, the song entered the Finnish Singles Chart at number 10, however, it only spent one week in the chart. In France, the song entered the French Singles Chart at number 14 on December 5, 1998 and eventually peaked at number five. After spending 20 weeks fluctuating in the singles chart, it was certified silver by the Syndicat National de l'Édition Phonographique (SNEP). In Germany, it peaked at number eight on the German Singles Chart and was certified gold by the Bundesverband Musikindustrie, denoting shipments of over 250,000 units. The song peaked at number seven in Ireland, where it spent 11 weeks in the Irish Singles Chart.
In Norway, "When You Believe" entered at number three on the VG-lista chart and peaked at number two, spending three consecutive weeks at the position. It was certified platinum by the International Federation of the Phonographic Industry (IFPI) and spent 15 weeks on the chart. The song peaked at number two in Sweden and Switzerland, spending 20 and 24 weeks on the singles charts, respectively. The IFPI certified the song platinum in Sweden and gold in Switzerland. "When You Believe" experienced high charting in the United Kingdom. It peaked at number four on the UK Singles Chart during the week of December 19, 1998 and spent 14 weeks on the chart. As of 2008, sales of the song in the UK are estimated at over 265,000 units.
The single's music video was filmed at the Brooklyn Academy of Music during the fall of 1998. The video begins with Houston entering a small arena as she begins to sing the song's first verse. As she finishes her part, Carey appears on the stage as well, performing the second bridge and chorus. The video is set in a dark studio accented by Egyptian settings, backdrops, and scenes inspired by The Prince of Egypt. An audience is on hand to emulate a concert-like-setting, cheering on both singers. Occasionally, home video clips of Carey and Houston appear throughout the video, as well as clips of the final moments of the film, during the splitting of the Red Sea. The video ends as the room is illuminated, and the two singers are joined by a large choir. As they complete the song, Carey and Houston receive a standing ovation from the crowd, and exit the studio together, walking side by side as they disappear in the distance. For the video, Carey and Houston both donned similar low-cut black gowns, while Carey sported a long straight hairstyle, and Houston a pixie cut.
The song's alternate video features a similar synopsis, where Houston begins the song on a large stone altar in the middle of an auditorium. As she finishes her verse, Carey is seen walking up the ramp in the background, joining Houston for her verse. They continue the song together, standing side by side and holding hands. After completing the song, both singer exit the auditorium together as in the first video, simulating two friends enjoying time with each other. Both videos are very similar, only the alternate version does not feature an audience, choir or images, only the duo singing together atop the stone altar. In this version of the video, Houston wears a long brown strapless gown, and features a shoulder length bob haircut. Carey on the other hand, features long cascading curls and dons an olive green gown.
The duo performed the song live on The Oprah Winfrey Show on November 26, 1998. Aside from the joint performance, Carey and Houston sang their own singles at the time, "I Still Believe" and "I Learned from the Best", respectively. Additionally, they sang the song live at the 71st Annual Academy Awards on March 21, 1999. Before the performance, they were due to rehearse together a few days before their scheduled appearance. Houston however, called in sick and had to miss the rehearsal. Reportedly, her excuse was not taken well, with academy executives calling it a "bullshit story." Conti, the academy's musical arranger, found a young female singer to take Houston's place, Janis Uhley. Before the performance, Carey walked down the stage in a white top and jeans, while choreographer Debbie Allen led the background singers. As they began the performance, Carey forgot the lyrics and stopped, as Uhley began singing in a "theatricality and gusto." Her boastful performance was not taken well by the directors, who called it "inappropriate and unnerving." After she was removed from the stage, a new date was chosen for the rehearsal, one that would accommodate both Carey and Houston. The next night, after they began the rehearsal, both singers had trouble performing the film version of the song. After hours of practice and confusion, they reached a compromise; they would sing a mash-up of the film and single versions, which featured an additional bridge and instrumentation by Edmonds. For the awards ceremony on the twenty first, Carey and Houston wore matching white gowns, symbolizing "humbleness and simplicity." At 5:55 pm, Houston entered the arena, performing her verse, followed by Carey. As the song's finale drew near, a full gospel choir joined the performance from large suspending golden scaffolding, all wearing large white tunics. After the original was nominated for the Academy Award, Schwartz refused to give Edmonds writing credits in nomination forms submitted to the academy. However, after being booked to perform at the awards show ceremony, Carey and Houston were told to perform the film version of the song, because it was the version nominated. To their dismay, both singers were not familiar with the original arrangement or key, because they had been performing the radio version throughout the winter. Conti composed a new version, which intermingled both versions. His idea was to help the duo learn the song's new arrangement, yet still satisfy the academy.
Glover performed "When You Believe" on American Idol on the "Divas" theme night on April 17, 2013. Glover's performance was met with praise from the show's judges and it was generally considered the best performance of the night.Rolling Stone wrote that Glover "got judges on their feet" with her "impeccable" performance.Mariah Carey was moved to tears by the performance and complimented Glover for doing the song justice.Nicky Minaj exlaimed at the end of the performance that "And that is how you do a Mariah Carey/Whitney Houston song".Randy Jackson considered Glover's performance "best vocal of the night". Likewise, Billboard called Glover's performance "best single showing of the night" and commented on the vocal delivery that "she knows precisely when to hit the sweet spot of a song, building up to that point with masterful restraint".MTV News commented that Glover "positively slay[ed]" the song.
In an interview for Chicago Music Magazine, Chloë Agnew described the lyrics of the song as "really incredible". She stated that "It is a songs that I listen to and wish I had written. It’s really so special. I think a lot of people have found strength and hope in the lyrics. Its been really rewarding to meet and talk to people at our meet and greet events come up and tell me how much that song means to them and how it has helped them".
"When You Believe" was recorded by The X Factor winner Leon Jackson in December 2007. The single was available to download from midnight after the result of the show on December 15, 2007, and a CD was rush-released mid-week, on December 19, 2007. This is unusual as most new singles are released on a Monday to gain maximum sales for the UK Singles Chart the following Sunday. Exceptions included the previous two X Factor winners whose were singles released in this fashion, in order for them to compete to be the Christmas number-one single, which they all became. A video for the single was made by each of the final four of the series; Jackson, Rhydian Roberts, Same Difference and Niki Evans. However, only the winner's version of the song and video was released.
The song ended 2007 as the year's fourth biggest-selling single in the UK and remained number one into 2008. However, this version of the song only managed to stay in the top 40 for seven weeks, despite being the staying atop the chart for three weeks. It also soon disappeared from the top 100, and was gone by late February.
The music video, like previous X Factor winners singles, is very simple, with Jackson singing the song in front of a large projection, with swooping shots of various landscapes behind him. It also features several clips from his time in The X Factor, from his first audition to the moment he was announced the winner and performed his single to close the series. Simon Cowell, Sharon Osbourne, Dannii Minogue, Louis Walsh, Dermot O'Leary and runner-up Rhydian Roberts all feature within the clips.
On December 23, 2007, it debuted at number one on the UK Singles Chart, making it the coveted Christmas number one with sales of over 275,000 copies. It stayed at number one for three weeks until it fell down to number five on its fourth week and then fell another ten places to number fifteen in its fifth week. According to The Official Charts Company, the song has sold 506,000 copies in the UK as of December 2012. Additionally, It also spent three weeks at the top of the Irish Singles Chart.