The St Barnabas Anglican Church, renowned for its beauty, was built in Warrington in 1872. The church has its origins with a wealthy local couple, Captain William Pitt and his wife Annie Gellibrand. They came from Australia, where William had been prominent in the Victorian Volunteer Staff. The Gellibrands, based in Tasmania, owned a large Otago sheep run. The first Anglican services in the district were held in the Pitt home. Annie Pitt's donation of land and money then allowed the construction of a church in the district.

Unfortunately the identity of the architect of St Barnabas is unknown. As church historian Charles Croot has remarked, its design indicates that it "was modelled as far as possible on an old English village church," although its "vertical weatherboards and shingle roof readily identify it as an early colonial New Zealand structure." Local man Benjamin Smith carried out the building work, assisted by the voluntary labour of Captain Pitt. It has been said locally that these two men may have also designed the building. They used local materials for most of the building, but the finer finishing touches - the bell and stained glass windows - were imported from England. Howell and Hay of The Octagon, Dunedin, made the rimu furnishings for the chancel.

The church opened on 11 November 1872 in the presence of numerous Otago clergy and the choristers of All Saints Church, Dunedin, and was consecrated by the bishop the following June.

St Barnabas Church has attracted many admirers and supporters over the years, the most notable being Samuel Nevill, Bishop of Dunedin from 1871 to 1919 and Anglican Archbishop of New Zealand from 1904. Nevill had great plans, only partly achieved, for a grandiose cathedral in his diocese, but he also had a great fondness for the country church at Warrington. At his own request, after his death in 1921 he was buried in the St Barnabas churchyard, which he had consecrated over forty years earlier.

It is reportedly due to Bishop Nevill that the church acquired the magnificent Bavarian stained glass windows in the back wall. He is said to have rescued them from storage in Dunedin, and they were installed in 1935, some years after his death, as memorials to Sophia and Annie Smith (relations of the Pitts) and to parishioner Jane Gardiner. Around this date also the original shingle roof was replaced with concrete tiles.

In more recent years, the church has undergone two extensive renovation projects; one in the 1970s and the other in the 1990s. Both projects have aimed to restore the church to its original glory rather than adapt it in any way. Besides necessary repairs and structural work, the major change in the first project was the replacement of the 1930s concrete roof tiles with wooden shingles, as in the original building. The 1990s project included restoration and conservation of the stained glass windows.

The St Barnabas Church has been served by clergymen from various locations over the years. From 1873 until 1905 it was cared for by the vicars of All Saints Church, Dunedin; and from 1905 until 1916 by the Warden and students of Selwyn College. Another donation from Annie Pitt then allowed the appointment of a resident vicar for some years. When he resigned in 1926 the church returned to the care of students and priests from Dunedin until 1936, when it was joined to the Port Chalmers parish. In 1959 a new arrangement began, the Anglican chaplain to the hospitals in the district also serving as vicar of St Barnabas. This lasted until 1974, when the church once again joined with Port Chalmers, where it remains at present.

Through its long life, this church has remained a centre of worship for locals and holidaymakers in the seaside village of Warrington. Its tranquil setting in spacious grounds, with large trees and a burial ground, adds to its charm. The church itself is an effective mixture of English and colonial styles, and its warm timbers and outstanding stained glass make it a building of particular beauty.