Lady Abney was of an Independent religious faith (known as
Congregational, after the 1830s), as were her husband Sir Thomas Abney and long-term houseguest
Dr Isaac Watts. Throughout the year when Sir Thomas held office as Lord Mayor, and Mary Abney was Lady Mayoress, they each had to practice
occasional conformity to the Church of England, as required by law. Similarly, as Lady of the Manor, Mary Abney had to uphold the general conformity of the parish church of the Stoke Newington Manor. Privately as an Independent, she was close friend of the religious revivalist
Selina Hastings, Countess of Huntingdon. The Countess formed her own independent religious group within the independent
Methodist movement, although working to compromise with the Anglican authorities. The Countess financed many revivalist causes, including the independent preacher
George Whitefield. In her later years, she helped sponsor the visit to Britain of
Olaudah Equiano, an African who was freed from
slavery in the British colonies. He had become an
abolitionist, and settled and married in England. Lady Abney is mainly remembered as the sponsor of
Isaac Watts, who lived in her household for 36 years. He is considered the first notable English hymnologist; he composed original works of Christian worship rather than using phrases from Biblical passages. His famous hymns include "
Joy to the World" and "
Our God, Our Help in Ages Past". Through this association, Lady Abney became part of a circle of many independent religious thinkers, including
Philip Doddridge. As one of Watts' main benefactors and likely his sole benefactor from 1734 until his death in 1748, Lady Mary enabled his work as a poet and scholar. His texts became standard in the New World as well as in Great Britain. Following Watts' death in 1748, Lady Mary had a memorial to him constructed at
Bunhill Fields, which she co-financed with neighbour
Sir John Hartopp. ==Death and charity==