Chicago-Lambeth Quadrilateral

The Chicago-Lambeth Quadrilateral, frequently referred to as the Lambeth Quadrilateral or the Lambeth-Chicago Quadrilateral, is a four-point articulation of Anglican identity, often cited as encapsulating the fundamentals of the Communion's doctrine and as a reference-point for ecumenical discussion with other Christian denominations. The four points are:

The Quadrilateral had its genesis in an 1870 essay by an American Episcopal priest, William Reed Huntington. Huntington's purpose in proposing these four elements was to establish "a basis on which approach may be by God's blessing, made toward Home Reunion," that is, with the Roman Catholic and Orthodox Churches.

The four points found their way into a resolution of the House of Bishops of the American Episcopal Church, meeting in Chicago in 1886. As passed there, the resolution reads as follows:

In 1888, the third Lambeth Conference (an international consultation of bishops of the Anglican Communion) passed Resolution 11. This was a scaled-back version of the resolution passed at Chicago two years earlier, more closely aligned with Huntington's original wording, and reads as follows:

The 1920 Lambeth Conference picked up and reiterated the points of the earlier documents in fresh language. The rewording of the fourth was radical:

The Episcopate was only expressly mentioned in the commentary which followed:

According to Michael Ramsey this conciliatory presentation aroused a great readiness to discuss reunion, but later declarations were more qualified and therefore frustrating for Free Churchmen.

The Quadrilateral has had a significant impact on Anglican identity since its passage by the Lambeth Conference. The Resolution came at a time of rapid expansion of the Anglican Communion, primarily in the territories of the British Empire. As such, it provided a basis for a shared ethos, one that became increasingly important as colonial churches influenced by British culture and values, evolved into national ones influenced by local norms. At the same time, it has been the locus of fervent debate, especially over its third and fourth points.

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