William Perkins (1558–1602) was an influential English cleric and Cambridge theologian, receiving a B.A. and M.A. from the university in 1581 and 1584 respectively, and also one of the foremost leaders of the Puritan movement in the Church of England during the Elizabethan era. Although not entirely accepting of the Church of England's ecclesiastical practices, Perkins conformed to many of the policies and procedures imposed by the Elizabethan Settlement. He did remain, however, sympathetic to the non-conformist puritans and even faced disciplinary action for his support.

Perkins was a prolific author who penned over forty works, many of which were published posthumously. In addition to writing, he also served as a fellow at Christ's College and as a lecturer at St. Andrew's Church in Cambridge. He was a firm proponent of Reformed theology, particularly the supralapsarian theology of Theodore Beza. In addition, he was a staunch defender of Protestant ideals, specifically the five solae with a particular emphasis on solus Christus and sola Scriptura.

Perkins was born to Thomas and Anna Perkins at Marston Jabbett in the parish of Bulkington, Warwickshire, England in 1558, the year in which the Protestant Elizabeth I succeeded her Catholic sister Mary as Queen of England. Perkins lived his entire life under Elizabeth I, dying one year before the Queen's death in 1603. Perkins's relationship with Elizabeth was ambiguous: on the one hand, she was Good Queen Bess, the monarch under whom England finally and firmly became a Protestant nation; on the other hand, Perkins and the other members of the Puritan movement were frustrated that the Elizabethan settlement had not gone far enough and pushed for further Reformation.

Little is known of Perkins' childhood and upbringing. Sometime in his early life he was rendered lame which forced him to write with his left hand. His family was evidently of some means, since in June 1577, at age 19, Perkins was enrolled as a pensioner of Christ's College, Cambridge being trained in the tradition of the Reformed scholastic framework. He would receive his BA in 1581 and his MA in 1584.

According to an unverifiable story, Perkins was convinced of the error of his ways after he heard a Cambridge mother say to her child, "Hold your tongue, or I will give you to drunken Perkins yonder." Whether or not the story is true, it is clear that Perkins had a religious awakening sometime between 1581 and 1584 during his time at Cambridge. Thomas Fuller's biographical profile of Perkins portrayed him as "very wild in his youth," skilled in mathematics, possessed of "a rare felicity in speedy reading of books," and preaching, early in his ministry, with a sternness that he mitigated in later years:

He would pronounce the word damn with such an emphasis, as left a doleful echo in his auditors' ears a good while after... . But in his older age he altered his voice and remitted much of his former rigidness; often professing that to preach mercy was that proper office of the ministers of the Gospel.

Perkins's sermons, wrote Fuller, "were not so plain but that the piously learned did admire them, nor so learned but that the plain did understand them."

Perkins thus began a lifelong association with the "moderate-puritan" wing of the Church of England which held views similar to those of the continental Calvinist theologians Theodore Beza, Girolamo Zanchi, and Zacharias Ursinus. Perkins's circle at Cambridge included Laurence Chaderton and Richard Greenham.