As an English composer and organist Weldon served at New College, Oxford, as "an" organist of the Chapel Royal, for St. Bride's on Fleet Street, as "the" organist of the Chapel Royal, as "the" organist for St. Martin-in-the-Fields, and as second composer to the Chapel Royal. Weldon won the first prize at New College for his setting of "The Judgment of Paris" having studied first with Walter and then Purcell. With a broad melodic range and texture as heard in the sprightly "From Grave Lessons" to the intense "O Lord Rebuke Me not," Weldon was a talented composer who never realized his full potential. Chromatic runs and phrases were well-placed and his use of minor passages scintillating. The liberties demonstrated in "The Last Judgment of Paris" however were not sustained throughout his career. Some of his compositions are simply monotonous.