If I am not mistaken, the pope approves the lectionary, the liturgical book that contains the Mass readings. Prior to Vatican II, the 1570 lectionary of Pius V was used. As a result of Vatican II, the lectionary has been revised twice, once in 1969 and again in 1981. source.
the 3=year Sunday and 2-year daily lectionary cycle are part of the liturgical reform initiated before WW2 and completed by Vatican II. The idea is to proclaim more of the OT and NT, so that together with the Office of Readings and readings for LOTH almost the entire Bible is proclaimed over the period.
Holland:
Thanks a bunch for replying! Any idea what would have to happen to make them want to change the readings? Is it at the request of the Pope?
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