Notwithstanding the ambiguity of its title, and the fact that it attacks the priests of all churches without moderation, it contends for the most part, at least explicitly, for no more than must be admitted by every Protestant.
Freethinking is a right which cannot and must not be limited, for it is the only means of attaining a knowledge of truth, it essentially contributes to the well-being of society, and is not only permitted but enjoined by the Bible.
In England this essay, which was regarded and treated as a plea for Deism, caused a great sensation, eliciting several replies, from among others William Whiston, Bishop Hare, Bishop Benjamin Hoadly, and Richard Bentley, who, under the signature of "Phileleutherus Lipsiensis", roughly handles certain arguments carelessly expressed by Collins, but triumphs chiefly by an attack on the trivial points of scholarship, his own pamphlet being by no means faultless in this very respect.
In 1724, Collins published the treatise Discourse of the Grounds and Reasons of the Christian Religion, with An Apology for Free Debate and Liberty of Writing prefixed.
Ostensibly it is written in opposition to Whiston's attempt to show that the books of the Old Testament did originally contain prophecies of events in the New Testament story, but that these had been eliminated or corrupted by the Jews, and to prove that the fulfilment of prophecy by the events of Christ's life is all "secondary, secret, allegorical, and mystical," since the original and literal reference is always to some other fact.
No less than thirty-five answers were directed against this book; the most noteworthy of which were those of Bishop Edward Chandler, Arthur Sykes and Samuel Clarke.
During Clarke's lifetime, fearing perhaps being branded as an enemy of religion and morality, Collins made no reply, but in 1729 he published an answer, entitled Liberty and Necessity.
It has been argued (see Jacobson, "The England Libertarian Heritage") that Collins was the unknown author of ten of "The Independent Whig" essays.