He appears to have been brought up as a Presbyterian, but having, as he says, been afflicted and abused by a false charge in his youth he was induced to become an Anglican clergyman in 1720, and in 1721 was sent by the Society for the Propagation of the Gospel in Foreign Parts as a missionary to Narragansett, Rhode Island.

The climate did not agree with Macsparran, and he was besides involved in a lawsuit with the non- conformists about glebe land which lasted for twenty-eight years.

On 4 Aug. 1751 Macsparran preached at St. Paul's Church, Narragansett, a sermon on the 'Sacred Dignity of the Christian Priesthood vindicated,' which he afterwards had printed at Newport, Rhode Island.

The object of his discourse was to correct sundry irregularities which had crept into the worship of the English church in America; but the congregational clergy chose to understand it as directed against themselves, and some vigorous pamphleteering ensued, in which, however, Macsparran declined to take part.

He longed in reality for preferment in Ireland, for which he knew himself to be peculiarly well qualified, as he could read and write, and upon occasion preach, in Irish.

This curious work, which is among the scarcest of Americana, was reprinted in an appendix to Wilkins Updike's History of the Episcopal Church in Narragansett, New York City, 1847, with portraits of Macsparran and his wife.