Lexington Parish, formed in 1779 and comprising the Episcopal congregations of Amherst County, was named in honor of the Revolutionary engagement at Lexington, Massachusetts. The Lexington Parish vestry book with entries from 1779 to 1880 has survived, though significant portions are missing, and gives great insight into the workings of the parish. In the first half of the nineteenth century, the most active congregations in the parish were St. Mark's, at New Glasgow (now Clifford); St. Luke's, at Pedlar Mills; and St. Matthew's, in the south end of the county.
In 1847, the Parish vestry recognized the need for a church at Amherst Court House (now the Town of Amherst). The decision to build a church at Amherst Court House is believed to have been made at the home of Dr. Landon Davies, which until the mid-twentieth century stood on the lot across the street from the church. Dr. Davies, Samuel M. Garland, William M. Waller, Taylor Berry, Zachary Tinsley, and Benjamin Taliaferro, among others, were active leaders in the first decades of Ascension's existence.
Construction began in 1847 on land given by Elijah and Maria Fletcher and was completed the following year under the direction of contractor Hickman Meredith. The names of the laborers, presumably enslaved, who built the church are unknown.
The original brick structure was a rectangular building with a high steeple. Over the years, a chancel, vestibule, bell tower, sacristy, organ chamber, and stained-glass windows were added. The Parish House, added in 1922, has been enlarged twice.
The absence of a chancel in the original building was probably a reflection of the strong evangelical bent of the Diocese of Virginia under the leadership of Bishops William Meade and John Johns. The church was consecrated by Bishop Johns on October 7, 1848. The following text from the occasion is preserved in the old vestry book.
Whereas, it hath pleased Almighty God to put into the hearts of the good people of the Parish of Lexington in Amherst County to build an house of worship to the honor of his Great Name. Therefore I, John Johns, Assistant Bishop of the diocese of Virginia on the seventh day of October 1848 do according to the solemn forms of the Protestant Episcopal Church in the United States consecrate the same to the worship of the Almighty God, by the name of Ascension Church, separating it henceforth from all unhallowed worldly and common uses and dedicating it to this service, for reading his holy word, for celebrating his holy sacraments, for offering to his glorious majesty the sacrifice of prayer and thanksgiving for blessing the people in his name, and for the performance of all other holy offices. And I humbly pray that he will accept this service at our hands, and bless it with such success as many tend most to his glory, and the furtherance of our happiness both temporal and Spiritual, through Jesus Christ our Lord. Amen.
According to local lore, George Christian and two other men were walking in the churchyard, trying to think of a suitable name for the new church. (Perhaps they were considering the name St. John's, in light of the other three churches in the parish being named for Saints Matthew, Mark, and Luke respectively.) Mr. Christian saw a piece of paper on the ground. When he picked it up, the first word he saw was “Ascension.” Immediately, he proposed that it should become the name of the church. His proposal was readily accepted.
The church's current banner depicts a chariot of fire and a dove descending, linking the story of Elijah's ascent to heaven with that of the coming of the Holy Spirit at Pentecost, ten days after the ascension of Christ.