Complex sentence: Lent and the Holy Week fasts are stricter than the other fasts in their discipline and for those who wish to take a vow of strict discipline for the fast of the Virgin Mary, may do so.
Split into simpler sentences: Lent and the Holy Week fasts are stricter than the other fasts in their discipline. Those who wish to take a vow of strict discipline for the fast of the Virgin Mary may also do so.