Isidor Philipp's arrangement of Widor's organ solo piece, "Toccata," for two pianos. Philipp became acquainted with Saint-Saëns's introduction after serving as the soloist for Widor's Piano Concerto No. 1, Op. 39, in 1886. Although Widor was 19 years Philipp's senior and a prominent figure in the music world, the two quickly became close and formed a compatible friendship. This was likely due to their shared musical inclination to respect the classics, their dislike of ostentation, and their resolute and diligent temperaments, which favored hard work and perseverance. As fellow professors at the Paris Conservatoire, they reportedly maintained a habit of having lunch together once or twice a week, often joined by mutual friends and acquaintances, for as long as 30 years. Widor composed a new Fantaisie for Piano and Orchestra, Op. 62, for Philipp, which Philipp premiered under Widor's baton, and Philipp made Widor's works a lifelong part of his repertoire. The two also frequently performed together on two pianos.

"Toccata" is the fifth (final) movement of Widor's Organ Symphony No. 5, Op. 42-1, and one of his representative works. It is marked Allegro, in 4/2 time, and in F major. With its brilliant and magnificent musical ideas, it has now become established as a crucial piece, particularly for European royal wedding ceremonies. In April 2011, the wedding of the current British Prince and Princess was broadcast worldwide and watched by 2 billion people, and it was Widor's Toccata that resounded most prominently at its most dramatic moment.

Philipp's arrangement reconstructs the vivid coloristic sense of stained glass and the clear, refreshing exhilaration entirely on two pianos. It is an arrangement of special value, comparable to the original work. It was also part of Philipp's own repertoire, and records show that he performed this work with his close friend Arnold Reitlinger and his pupil Cécile Deroche, among others.