"O Saviour of the World" is a revered Anglican anthem composed by Sir John Goss, who was Organist of St Paul's Cathedral and a prominent figure in 19th-century English church music. Known for its devotional and accessible style, the piece is a classic example of Victorian sacred music, often performed during Communion services. Its enduring popularity is attributed to its poignant melody and harmonic simplicity, making it suitable for both large cathedrals and smaller parish choirs, as hinted at in the user's description.