Here's the text of the letter:
I received your favor of the 20th instant last evening, and hasten to give you the information, which you desire.
Truro Parish is the one in which Mount Vernon, Pohick Church, and Woodlawn are situated. Fairfax Parish is now Alexandria. Before the Federal District was ceded to Congress, Alexandria was in Fairfax County. General Washington had a pew in Pohick Church, and one in Christ Church at Alexandria. He was very instrumental in establishing Pohick Church, and I believe subscribed largely. His pew was near the pulpit. I have a perfect recollection of being there, before his election to the presidency, with him and my grandmother. It was a beautiful church, and had a large, respectable, and wealthy congregation, who were regular attendants.
He attended the church at Alexandria when the weather and roads permitted a ride of ten miles. In New York and Philadelphia he never omitted attendance at church in the morning, unless detained by indisposition. The afternoon was spent in his own room at home; the evening with his family, and without company. Sometimes an old and intimate friend called to see us for an hour or two; but visiting and visitors were prohibited for that day. No one in church attended to the services with more reverential respect. My grandmother, who was eminently pious, never deviated from her early habits. She always knelt. The General, as was then the custom, stood during the devotional parts of the service. On communion Sundays, he left the church with me, after the blessing, and returned home, and we sent the carriage back for my grandmother.
It was his custom to retire to his library at nine or ten o'clock where he remained an hour before he went to his chamber. He always rose before the sun and remained in his library until called to breakfast. I never witnessed his private devotions. I never inquired about them. I should have thought it the greatest heresy to doubt his firm belief in Christianity. His life, his writings, prove that he was a Christian. He was not one of those who act or pray, "that they may be seen of men." He communed with his God in secret.
My mother resided two years at Mount Vernon after her marriage with John Parke Custis, the only son of Mrs. Washington. I have heard her say that General Washington always received the sacrament with my grandmother before the revolution. When my aunt, Miss Custis [Martha "Patsy"] died suddenly at Mount Vernon, before they could realize the event, he knelt by her and prayed most fervently, most affectingly, for her recovery. Of this I was assured by Judge Washington's mother and other witnesses.
He was a silent, thoughtful man. He spoke little generally; never of himself. I never heard him relate a single act of his life during the war. I have often seen him perfectly abstracted, his lips moving, but no sound was perceptible. I have sometimes made him laugh most heartily from sympathy with my joyous and extravagant spirits. I was, probably, one of the last persons on earth to whom he would have addressed serious conversation, particularly when he knew that I had the most perfect model of female excellence ever with me as my monitress, who acted the part of a tender and devoted parent, loving me as only a mother can love, and never extenuating or approving in me what she disapproved of others. She never omitted her private devotions, or her public duties; and she and her husband were so perfectly united and happy that he must have been a Christian. She had no doubts, no fears for him. After forty years of devoted affection and uninterrupted happiness, she resigned him without a murmur into the arms of his Savior and his God, with the assured hope of his eternal felicity. Is it necessary that any one should certify, "General Washington avowed himself to me a believer in Christianity?" As well may we question his patriotism, his heroic, disinterested devotion to his country. His mottos were, "Deeds, not Words"; and, "For God and my Country."
With sentiments of esteem,
I am, Nelly Custis-Lewis