Jesus himself taught us how to behave: Let your manner of speaking be yes, yes, or no, no; whatever goes beyond this, proceeds from an evil principle. In dealing with others, a man's word must suffice. Yes must be yes and no must be no. The Lord wanted to enhance the value and strength of the word of a good man who feels committed to what he says.
Our word and our actions as Christians and honest men must have great value in the eyes of others, because we must always and in everything seek the truth, fleeing from hypocrisy and duplicity. In the normal situations of life, the word of the Christian should be enough to give all the necessary force to what he affirms or promises. The truth is always a reflection of God and must be treated with respect. If we get into the habit of always speaking the truth, even in matters that seem unimportant, our word will have a great force, "like the signature of a notary", which is not questioned. Thus we imitate the Lord.
Far removed from what a Christian should be is the double-minded man, inconstant in all his ways,4 who presents a personality or ideas, like actors, according to the audience before him. He is a double-minded man," comments St. Bede, "who here wants to rejoice with the world, and there to reign with God.
Today it is especially urgent for the Christian to be a man, a woman, of one word, of "one life", without using masks or disguises in situations in which it can be costly to maintain the truth, without worrying excessively about "what people will say" and throwing away human respects, rejecting all hypocrisy. Truthfulness is the virtue that inclines one to always tell the truth and to manifest oneself outwardly as one is inwardly, teaches St. Thomas Aquinas. However, there will be cases in which we are not obliged to manifest the truth, and sometimes it is even a grave duty of justice not to reveal it: it can be for reasons of professional secrecy, public safety or other serious reasons, among which the sacramental confidentiality of the confessor and that which refers to spiritual direction stand out. In these cases there are various ways of concealing the truth, without incurring in a lie. Also, when the questioner has no right to know the truth and, in extreme cases, acts as an unjust aggressor, losing even the right not to be deceived. But, "let us not forget, moreover, that it is often our fault that we are asked indiscreet questions. If we were to keep more recollection and silence, we would not be asked them or they would be asked very rarely".
Let us imitate the Lord in his love of truth. Let us formulate the resolution to flee from lies and from everything that sounds false and hypocritical. "You read in that dictionary the synonyms of insincere: "ambiguous, deceitful, deceitful, sly, cunning".... -You closed the book, while you prayed to the Lord that those adjectives could never be applied to you, and you proposed to refine yourself even more in this supernatural and human virtue of sincerity".