Final answer:
The two main forms of sacred Renaissance music are the Masses and Motets, both of which played a central role in the era's liturgical practices and choral expressions.
Step-by-step explanation:
The two main forms of sacred Renaissance music are the Masses and the Motets. Sacred music in the Renaissance period featured the mass as a principal liturgical form that endured throughout the era. Motets, on the other hand, allowed composers to express their creativity with a more flexible textual and musical structure. Masses formed the very core of the liturgical music of the Church, while motets, which could be based on sacred or secular themes, often included complex polyphony and were highly prized for their artistic expression.
Despite the popularity of other secular forms towards the end of the Renaissance period, such as the madrigal, it was the mass and the motet that were the primary forms of sacred music during this time. The motet in particular displayed the changing musical styles with increasing reliance on harmonious intervals like the third, and a move towards more intricate polyphony.