Formal and dignified
Another term for High Mass.
An agreement made in 1643 between the English Parliament and the Scottish Covenanters during the English Civil War, by which the Scots would provide military aid in return for the establishment of a Presbyterian system in England, Scotland, and Ireland. Although the Scottish support proved crucial in the Parliamentary victory, the principal Presbyterian leaders were expelled from Parliament in 1647 and the covenant was never honoured
a solemn occasion
una promesa solemne
hacer* una promesa/un juramento/un voto solemne