Byrd supported the Petre family's covert Catholic worship by composing a comprehensive repertory of choral music to be sung in the private chapels at Ingatestone and nearby Thorndon Hall, the other Petre family property. The compositions included two sets of motets called Gradualia (1605 and 1607) and a set of three Mass settings, such as the Mass for Four Voices (1592–3), works first heard at Ingatestone that are now considered to be some of the finest examples of Tudor music.
Byrd supported the Petre family's covert Catholic worship by composing an extensive choral repertoire to be sung in private chapels at Ingatestone and Thorndon Hall, another Petre property. The compositions included two sets of motets titled Gradualia (1605 and 1607) and a set of three Mass settings, such as the Mass for Four Voices (1592–3), which were first performed in Ingatestone and are now considered among the finest examples of Tudor music.