The St John of God Chapel was designed by Alfred and Sidney Luttrell for the Mount Magdala Institute in 1910-1912. The Luttrell brothers established one of the foremost Edwardian architectural firms after their arrival in New Zealand in 1902. While their chief contribution to New Zealand architecture is seen as the introduction of the Chicago 'skyscraper' style, manifest in their buildings for the New Zealand Express Company, they were also well known for their use of concrete, design of racecourse buildings and as the unofficial architects for the Roman Catholic Diocese in Christchurch.

The Luttrells' design of the chapel at St John of God is an example of the Perpendicular Gothic style, revived by the English architect G F Bodley during the 1870s. Elements of this style can be seen in the tracery and the battlemented tower, which is the dominant feature of the chapel, which was built in bluestone with Oamaru stone dressings. Also significant is the open dark-stained timber roof and the collection of stained glass windows designed by the German firm F.X. Zettler and Co.

The Mount Magdala Institute had been established by Father Ginaty in 1886, to provide a home for women and girls. The Sisters of the Good Shepherd, who ran the institution, took in women recently released from prison, orphans, and 'unruly' girls and provided them with a home and work. At its peak, during the 1930s, Mount Magdala housed 500 people, and the complex included an industrial school and housing for the elderly. In the 1960s girls were referred to the Institute from the Department of Social Welfare. This mixture of inhabitants affected the design of the chapel. As separate entrances and seating were required for the sisters, the orphans and women in the reformatory, the transepts and nave are similar in size and the principal altar is arranged so that it can be viewed by all.

In the second half of the twentieth century ideas about the appropriate way to care for delinquent children changed and large institutions such as Mount Magdala began to close. In 1966 Mount Magdala was taken over by the Brothers of St John of God. The Brothers established the St John of God Hospital on the site, to care for those with long-term physical disabilities or terminal illnesses, and the elderly. The chapel had been physically linked to the first hospital, which was demolished in 2000. Now the St John of God Chapel stands separate from the new hospital.

The St John of God Chapel is significant as part of New Zealand's religious and welfare history. It is the largest ecclesiastical building designed by the Luttrell Brothers and has been described as 'Alfred Luttrell's most elaborate and individual interpretation of the Perpendicular Gothic style' (McEwan, 1988: 151). The stained glass windows designed by F.X. Zettler and Co are of particular significance and are the second largest collection of Zettler windows in New Zealand. Also buried in the chapel are two leading Christchurch churchmen, Father Ginaty, who founded the Mount Magdala Institute and Bishop Brodie (1871-1943), the first New Zealand-born Bishop of Christchurch.