"A Treatise on God's Free Grace and Man's Free Will" by William Perkins offers an exploration of theological concepts from a Reformed perspective, particularly focusing on the interplay between divine grace and human will. Perkins, one of the foremost leaders of the Puritan movement in the Church of England during the Elizabethan era, critiques the Roman Catholic Church's views on grace and free will, arguing that they undermine the sovereignty of God's grace.

Perkins identifies two primary ways in which the Roman Catholic doctrine is seen as opposing the grace of God. Firstly, he argues that it overemphasizes the role of human free will while diminishing the role of divine grace. He contends that human will, in its natural state, is incapable of performing godly actions without being transformed by God's grace. This transformation is necessary for salvation and godliness, as human nature alone is insufficient for spiritual understanding or repentance