Whether secret abstinence ought to be made known, without telling a lie about it, to those who ask, and whether what has once been declined may be taken in hand.
And to bring forward some instances from our unavoidable and almost daily wants which with all our care we can never so guard against as not to be driven to incur them whether with or against our will: what, I ask you, is to be done when, while we are proposing to put off our supper, a brother comes and asks us if we have had it: is our fast to be concealed, and the good act of abstinence hidden, or is it to be proclaimed by telling the truth? If we conceal it, to satisfy the Lord's command which says: “You shall not appear unto men to fast but unto your Father Who is in secret;” and again: “Let not your left hand know what your right hand does,” we must at once tell a lie. If we make manifest the good act of abstinence, the word of the gospel rightly discourages us: “Verily I say unto you, they have their reward.” But what if any one has refused with determination a cup offered to him by some brother, denying altogether that he will take what the other, rejoicing at his arrival, begs and intreats him to receive? Is it right that he should force himself to yield to his brother who goes on his knees and bows himself to the ground, and who thinks that he can only show his loving heart by this service, or should he obstinately cling to his own word and intention?
Source: Conferences (New Advent)