The Canadian Encyclopedia says this about the "early" organ works of Healey Willan (1880-1968): With the music for organ one enters a different world. Here Willan was thoroughly at home and made a significant and lasting contribution. One work stands out: the monumental "Introduction, Passacaglia and Fugue" of 1916. It represents the culmination of Willan's first period of organ composition, which started ca 1906 with a Fantasia on 'Ad coenam agni.' The Preludes and Fugues in C minor and B minor and the "Epilogue" are the other major works from this period. While not exploring the possibilities of the instrument as searchingly as his masterpiece, they are idiomatic and very typical of their time. They combine an innate Englishness (with a Stanfordian flavour) and a European chromaticism that can be found in Reger and Karg-Elert.
Born in England, Willan became organist-choirmaster of Toronto's largest church, St. Paul's, Bloor Street, but it was his royalties as a composer which allowed him to leave "low church" St. Paul's in 1921 and to become Precentor of the Church of St. Mary Magdalene (Toronto).
"Prelude on 'Thee we adore'" was written in 1954 and published by Concordia in 1956. It is based upon the Solesmes version of the melody, so, it may be slightly "different" than some of us are accustomed to.
I found this to be very "fussy," and difficult not to make it sound "busy." You'll have an easier time of it if you play the left hand solo on the "upper manual," and the accompaniment on the "lower" one.
In this performance, I used the Swell strings for the accompaniment and the Solo cor anglais with tremulant for the melody.
The "2s against 3s" and the tricky phrasings and patterns are harder than they sound. :-)
The text of the first verse is given in the First Comment.
The score is attached below, as well as series of photos of Healey Willan.