"Speaking in Tongues" is the fifth single from indie rock band Arcade Fire's third album, The Suburbs. It did not appear on the original track listing, but showed up on the deluxe edition as a bonus track.

There is a direct reference to T.S Eliot's The Waste Land: "Hypocrite reader, my double, my brother", himself quoting Baudelaire's To the Reader: "— Hypocrite lecteur, — mon semblable, — mon frère!"

The title itself is a reference to the Bible (Acts 2:4 ; 1 Corinthians 14:18) to a phenomenon called glossolalia, which is believed to be a divine language unknown to the speaker. It is also a reference to the 1983 album of the same name by Talking Heads, the former band of guest singer David Byrne.

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