It created one of the pioneer statutes passed by the legislative body of an organized colonial government to guarantee any degree of religious liberty.

It was revoked in 1654 by William Claiborne, a Virginian who had been appointed as a commissioner by Oliver Cromwell; he was an Anglican, a Puritan sympathizer, and strongly hostile to the Catholic Religion.

[2] The Calverts intended the colony to function both as a haven for English Catholics fleeing religious persecution and as a source of income for themselves and their descendants.

Along with giving instructions on the establishment and defense of the colony, he asked the men he appointed to lead it to ensure peace between Protestants and Catholics.

[5] The Ordinance of 1639, Maryland's earliest comprehensive law, expressed a general commitment to the rights of man, but did not specifically detail protections for religious minorities of any kind.

Cecil Calvert, 2nd Baron Baltimore, quickly regained power, but recognized that religious tolerance not specifically enshrined in law was vulnerable.

[8] This recognition was combined with the arrival of a group of Puritans whom Calvert had induced to establish Providence, now Annapolis, by guaranteeing their freedom of worship.

[9] Partially to confirm the promises he made to them, Calvert wrote the Maryland Toleration Act and encouraged the colonial assembly to pass it.

[3] The law was very explicit in limiting its effects to Christians:[10] ... no person or persons ... professing to believe in Jesus Christ, shall from henceforth be anyways troubled, Molested or discountenanced for or in respect of his or her religion nor in the free exercise thereof within this Province ...Settlers who blasphemed by denying the Trinity or the divinity of Jesus Christ could be punished by execution or the seizure of their lands.

In 1658, a Jew named Jacob Lumbrozo was accused of blasphemy after saying that Jesus was not the son of God and that the miracles described in the New Testament were conjuring tricks.

In addition to repealing the Maryland Toleration Act with the assistance of Protestant assemblymen, Claiborne and Bennett passed a new law barring Catholics from openly practicing their religion.

"[9] It was not until the passage of the signed First Amendment to the Constitution over a century later that religious freedom was enshrined as a fundamental guarantee,[3] but even that document echoes the Toleration Act in its use of the phrase, "free exercise thereof".