W'hile at Mamaroneck he was called to St. Thomas's, accepted, and served gratuitously, till 1822 when through Bishop Hobart's recommendation he was invited by Bishop White of Pennsylvania, to become his personal assistant in the " three United churches " of Christ church, St. Peter's, and St James's in Philadelphia of which he was also Rector. This invitation Mr. de Lancey accepted, and in April 1822 took up his residence in that city. He thus became from June 1821

to April 1822, about ten months, the first clergyman regularly in charge of St. Thomas's, Mamaroneck.

In 1823 a frame church with pointed windows and a low tower was erected, and consecrated on the 17th of June in that year by the Rt. Rev. John Henry Hobart, then the Bishop of New York. The expense was mainly borne by Mr. John Peter de Lancey, Mr. Peter Jay Munro, and Mr. Purdy the father of the present Mr. Samuel G. Purdy, of Harrison. The clergy present were the Rev. Lewis P. Bayard and the Rev. Lawson Carter, both warm friends, and the former a relative of Mr. de Lancey and the wife of Mr. Munro. A cut of it is given which shows the edifice as it was originally. It was enlarged some years later, in 1835 by a chancel, and again in 1857 -- atthe chancel end by an addition containing another window on each side, and so remained until removed, and subsequently torn down, on the erection of the present striking and exceedingly handsome stone church, built at their sole expense and presented to the church corporation, by Mr. James M. Constable and his children as a memorial of his wife and their mother the late Mrs. Henrietta Constable, who departed this life February 11'", 1884. The Cornerstone was laid December 4th, 1884, by the Rt.