Before the Reformation, English churches sang the psalms to Gregorian plainsong tones in Latin, a system built for unmetered prose text rather than rhymed verse. When the Church of England moved to English language worship, composers needed a way to keep singing prose psalms, now in English translation, without switching to rhymed metrical paraphrase, which many church musicians considered a lesser vehicle for scripture's own words.
Early efforts, including John Merbecke's mid sixteenth century adaptation of plainsong to the new English Book of Common Prayer, worked directly from the older Latin chant tradition, adjusting its melodic formulas to fit English prose rather than discarding the plainsong inheritance outright. Anglican chant as it later developed kept this basic principle, a short recurring melodic formula sung to prose text, but reworked it for four part harmony in the newer Western tonal idiom and added the technique of pointing, marking the printed text to show exactly how its syllables divide across the notes of the chant. A single Anglican chant, often only a few bars of music, can therefore be reused across an entire psalm, its pointing adjusted line by line so the fixed tune fits prose of varying length and rhythm, a solution that let English cathedral and parish worship keep singing the psalter in full without either abandoning chant or forcing scripture into rhymed verse.