Provoost was educated at King's College, now known as Columbia University, graduating in 1758, and promoted to Master of Arts in 1761.

[6] Samuel was fluent in Hebrew, Greek and Latin, and while he was at Cambridge he learned French and Italian gaining the distinction as a linguist.

[8][9] In February 1766, Provoost was ordained a deacon at the Chapel Royal of St James's Palace in Westminster and a priest in March 1766.

Provoost's dry preaching style, along with his support for American independence, offended some church members and in 1769 a motion was made in the vestry to dispense with his services.

[10] During his 13 years there he preached occasionally in neighboring churches, and joined his neighbors in their pursuit of the British after the burning of the town of Esopus, but he declined offers to serve as a delegate to the Provincial Congress and as chaplain of the New York Constitutional Convention of 1777, as well as the rectorship of churches in Charleston, South Carolina, and Boston.

[11] In 1783, after the end of the American Revolutionary War, the outspoken Tory rector of Trinity Church, Charles Inglis (the future first Anglican Bishop in Canada), left for England and was replaced by assistant rector Benjamin Moore, who had stayed at Trinity through the British occupation.