Mendelssohn was commissioned to write his setting of this text by the authorities in Liège to mark the 600th anniversary of the Feast of Corpus Christi on June 11th 1846.
At the time of this commission, Mendelssohn was working on his oratorio Elijah for the 1846 Birmingham Festival, which was in August. He interrupted his work on that to compose Lauda Sion and to conduct the first performance in St. Martin’s Church, Liège. He must have worked at great speed, because in May and June 1846 he was also directing music festivals in Aachen and Cologne. Elijah was of course completed on time, but with such work-pressure it is not surprising that a year hence he would be recovering from a nervous break-down; indeed thereafter he had only a few months to live.