Tradition
John Cassian
Conferences
Conference 21 › Chapter 24
A question on the different ways of keeping Lent.
Germanus: What is the reason why Lent is kept for six weeks, while in some countries a possibly more earnest care for religion seems to have added a seventh week as well, though neither number when you subtract Sunday and Saturday, gives the total of forty days? For only six and thirty days are included in these weeks.
Source: Conferences (New Advent)