Leper's squint

A hagioscope (from Gr. άγιος, holy, and σκοπεῖν, to see) or squint is an architectural term denoting a small splayed opening or tunnel at seated eye-level, through an internal masonry dividing wall of a church in an oblique direction (south-east or north-east), to enable one or more worshippers in side-chapels, private manorial chapels, chantry chapels at the east ends of the aisles, or other parts of the church from which the high altar in the chancel was not visible, to view the elevation of the host, in Roman Catholic and pre-Reformation usage, the most sacred part of the mass at which point a bell was rung and the congregation was required to make the sign of the cross. Where such areas were separated from the high altar not by a solid wall of masonry but by a transparent parclose screen, a hagioscope was not required as a good view of the high altar was available to all within the sectioned-off area concerned. Where a squint was made in an external wall so that lepers and other non-desirables could see the service without coming into contact with the rest of the populace, they are termed "leper windows".

Where the congregation of a church is united in the nave there is no use for a hagioscope. However when parts of the congregation separated themselves for purposes of social distinction, by use of walls or other screens from the chancel, or nave, and from the main congregation, such a need arose. In medieval architecture hagioscopes were often a low window in the chancel wall and were frequently protected by either a wooden shutter or iron bars. Hagioscopes are found on one or both sides of the chancel arch; in some cases a series of openings has been cut in the walls in an oblique line to enable a person standing in the porch (as in Bridgwater church, Somerset) to see the altar; in this case and in other instances such openings were sometimes provided for an attendant, who had to ring the Sanctus bell when the Host was elevated.

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