The Anglican church (or the Church of England) was the official church of the colony of Virginia. In colonial Virginia, during what has been called “The Great Awakening” – a period of increased religious fervor during the 18th century that was as a precursor to the American Revolution, Anglican priests taught that virtue led to happiness. The Anglican ministers in Virginia often relied upon the sermons of the Archbishop of Canterbury, Dr. John Tillotson (1630-1694). The Archbishop of Canterbury was the senior bishop and principal leader of the Church of England, and Tillotson served in this capacity from 1691-1694. His Works were read not only by ministers, but by many parishioners. Tillotson taught that, “Virtue and Goodness are so essential to happiness that where these are not, there is no capacity of it.”
The law in Virginia at that time was that you must attend church once a month or be subject to a fine, so the church pews were usually full. Thus, Anglican Virginians, such as George Washington and Thomas Jefferson, would have heard these types of sermons when they attended church.
For example, Charles Clay, the Anglican minister in Thomas Jefferson’s parish, who presided over Jefferson’s mother’s funeral in 1776, was a follower of Tillotson. Clay taught his congregations to “Give …all diligence to grow in grace & increase in Virtue… [which brings] true Happiness.” (Virginia-born Clay was a parish priest in St. Anne’s Church, Albemarle County, from 1769 to 1785).
Of course while Washington and Jefferson didn’t attend church every Sunday, they were exposed to these teachings. From their study of history, the reformation and the enlightenment, is it any wonder then that Washington and Jefferson embraced these same principles and reflected them in their writings?
George Washington wrote, "[T]here is no truth more thoroughly established, than that there exists . . . an indissoluble union between virtue and happiness." (First Inaugural Speech (1789). And in his Farewell Address he stated, "Can it be that Providence has not connected the permanent felicity [happiness] of a nation with its virtue?"
Thomas Jefferson wrote to a friend, “The order of nature [is] that individual happiness shall be inseparable from the practice of virtue.” (Letter to M. Correa de Serra, 1814). In another letter, almost quoting Tillotson, Jefferson stated: “Without virtue, happiness cannot be.” (Letter to Amos J. Cook, 1816). And, on another occasion he wrote, “Happiness is the aim of life. Virtue is the foundation of happiness.” (Letter to William Short, October 31, 1819).
With this in mind, Jefferson might have penned this most famous line of the Declaration of Independence to read, "We hold these truths to be self‑evident, that all men are created equal, that they are endowed by their Creator with certain unalienable Rights, that among these are Life, Liberty and the pursuit of Virtue."
See: Jacob Blosser, “Pursuing Happiness in Colonial Virginia,” Virginia Magazine of History and Biography, Vol. 118, No. 3 (2010) p. 229, p. 243 n. 24).