Council of Trent

CANON VII.--If any one saith, that the ceremonies, vestments, and outward signs, which the Catholic Church makes use of in the celebration of masses, are incentives to impiety, rather than offices of piety; let him be anathema.

-Council of Trent, Session 22 (17 Semptember 1562), in Decrees of the Ecumenical Councils, vol. 2, Trent to Vatican II, ed. and trans. Norman P. Tanner (Washington, DC: Georgetown University Press, 1990), 731-741.

This Canon asserts the Church's authority to establish rites. I think I stumbled back to this through Denzinger. There's a connection here in Canon Law, references in Paschang too.

The larger theological import is that Trent asserts the Church's spiritual authority which pertains to the establishment of sacramentals, and their relationship to Christ's sacrifice through the Church.