GENEVAN 12 (or DONNE SECOURS, see 12) was the tune originally selected for the text for singing at the Evanston Assembly. That tune is set to the Harkness text in many hymnals.
V. Earle Copes (PHH 302) composed VICAR in 1963 as a setting for Harkness's text for inclusion in the American Methodist Hymnal of 1966. The tune is named for the composer's father, Archie Vicar Copes (usually called by his middle name).
VICAR is a vigorous unison tune with distinctive rhythms and a colorful harmonization, and is representative of what Erik Routley (PHH 31) called the "clean-limbed" style. Organists should favor the soprano line to support this fervent prayer. Try having the choir's sopranos sing the tenor line an octave higher as a descant on stanza 5.