The Holy Rule
On the Keeping of Lent
The life of a monk ought always to be a Lenten observance. However, since such virtue is that of few, we advise that during these days of Lent he guard his life with all purity and at the same time wash away during these holy days all the shortcomings of other times. This will then be worthily done, if we restrain ourselves from all vices. Let us devote ourselves to tearful prayers, to reading and compunction of heart, and to abstinence.
During these days, therefore, let us add something to the usual amount of our service, special prayers, abstinence from food and drink, that each one offer to God "with the joy of the Holy Ghost" (1 Thes 1:6), of his own accord, something above his prescribed measure; namely, let him withdraw from his body somewhat of food, drink, sleep, speech, merriment, and with the gladness of spiritual desire await holy Easter.
Let each one, however, make known to his Abbot what he offereth and let it be done with his approval and blessing; because what is done without permission of the spiritual father will be imputed to presumption and vain glory, and not to merit. Therefore, let all be done with the approval of the Abbot.