The Church of God a Kingdom is, L. B. C. L. Muirhead. [The Church of Christ.] Contributed to the Yattendon Hymnal, 1899, No. 61, with the note at p. 18: "By Lionel B. C. L. Muirhead, 1898; written for this book: after Van Eyck's picture of the "Worship of the Lamb." This picture, now in the Cathedral of St. Bavon at Ghent, was begun by Hubert van Eyck about 1420, and finished by his brother Jan in 1432 (the reproduction by the Arundel Society is one of the best of their issues). The hymn is repeated in The English Hymnal, 1906, No. 488. [Rev. James Mearns, M.A.]
--John Julian, Dictionary of Hymnology, New Supplement (1907)