"Bridge Over Troubled Water" is a song about offering unwavering support to someone in their darkest hour, promising to be there for them no matter how deep the waters of their troubles. Paul Simon wrote the song, drawing inspiration for the title from a gospel line and for parts of the melody from a Bach hymn. Although Simon initially wrote it on guitar, he used the piano to reflect the gospel influence and suit Art Garfunkel's voice, who delivers the powerful lead vocal performance. The final verse, added at Garfunkel's suggestion, was inspired by Simon's then-wife. It's a song that speaks to the profound comfort of a steadfast presence in times of struggle.